Bosch Injectors

I know the standard Bosch 0280150450 20vT injectors were discontinued in 2008. My question is has anybody found a replacement? I've seen reference to Lucas Denso and they seem to produce a 360 cc injector but the impedance is 12 rather than 16 Ohms and I suspect this would cause a problem.

My current injectors are visibly dripping; fuel rail drops from 3 bar to 2 bar in 10 mins. After half an hour all pressure lost. This is causing hard starting from flooding (I can smell fuel on the engine oil) and I can hear vapour being pushed back in to a full tank of fuel if I cycle the ignition key several times before trying to start. I've changes the O rings, filter baskets etc. and they have a good uniform spray pattern but warm start is just a pain.

Really don't want to buy second hand from ebay as they could equally be shot and don't trust units from the far east.

Any advice?

You could try having them cleaned, eg. https://www.asnu.com/service-centres

or buy a cheap ultrasonic cleaner from ebay and DIY.

I discussed this very subject with Joe only the other day (though I don't recall which injectors he was asking about, the impedances were very similar). He had come across a car with 12 ohm impedance which had been running for some time without issue.

Here's the (electronics engineer hat on) deal.

1) current through a circuit is proportional to the loop resistance of the circuit - in this case, the current therefore would increase by about 33%.
2) power dissipated in a circuit is equal to the voltage across that circuit multiplied by the current - so the power dissipated by each injector will be around 16W, most of which is absorbed through the manifold and the fuel flowing through the injector. We can assume that Lucas are happy with that sort of load.
3) the injectors are switched on using a transistor in series with the injector coil. That transistor - one per injector - is in the ECU housing. The transistor is always either off (and dissipating no power) or hard on, with a voltage drop of about 0.2v (guessing here from 1990's power transistor spec; I don't know which transistor is actually used) and so when it's turned on, the power dissipated by the transistor's internal resistance will be around 200mW; no great problem as it's bolted on to a heat sink on the case of the ALU.
4) the bad news: between those two extremes, the transistor is either switching on or off, and it can't do that instantaneously. The time it takes to do that depends on the transistor characteristics (which I don't know), the circuit configuration (which I don't know) and the speed the engine is running. While it's switching, it's not a switch, it's another resistor in the circuit and it's dissipating like mad. As the engine runs faster, the proportion of the time that it spends in this switching time vs either on or off increases, so the worst time is when you're running maximum revs - where each transistor would be dissipating around 33% more than the ECU was designed to...

Ok, we do have a couple of points: first that Joe knows of at least one case where they have been successfully run for some time (I don't know how long). Secondly, no designer worth his salt would use transistors running particularly close to their limits, particularly where the environment in which they would operate is so harsh, and where they're expected to work for decades. Personally, I'd spec at least two hundred percent overload, and try and get five hundred past the production engineers (they're more expensive!).

So, my *BEST GUESS*, no guarantees, is that at normal speeds there will be no issues. I'd check the ECU after a fast run with the correct injectors and see if it got too hot to touch; if it does, I would be very wary of changing to those lower impedance injectors. If it feels ok, change them and then do the same test. 'Too hot to touch' is about 60C at the heatsink, so the transistor cores will be at maybe 80 or 90C. Most electronics are specified for 0-70C, those for cars from -20 to +85. Running components at elevated temperature degrades their operation... make you own mind up

Neil

p.s. Injectors with impedances in the 10-14 ohm range are referred to as 'high impedance'. Don't even think about fitting 'low impedance' injectors with an impedance of around an ohm.

Thanks GrahamL. I thought about that and it might be a solution - I ran 1 liter of acetone through each injector at 3 Bar pressure, alternating constant flow and pulsing using a pp9 battery. It improved the spray pattern such that they are all now the same and on a cold start the engine now revs out to 1500 revs and then progressively drops down to 750 rpm idle. At that point I thought I might have fixed it, it was that good! However whilst cold start has improved impressively it has turned out to make no difference to the clearly observable injector tip leak So my concern is spending money on injectors that might just be past it - 124k miles.

Thanks Neil. What you have said all makes sense, I remember my V/IR and tbh I had not given a thought to the injector heat dissipation. My concern was the effect it might have on the ECU transistors but as you have described it might be worth pursuing. The only source I can find for the Lucas Denso @350 cc 12 Ohm at present is the US, the price is good but as usual they don't respond to mails. I'll give it a bit longer then give them a call.

If its of any use- on the issue of sonic cleaning -I had an injector issue last year - and had all of the injectors sonic cleaned/patterns checked etc. Maybe that made some of them healthier/spray better.

The non working one however still didn't work - they seem to have the tendency to be fine when cooler- but when hotter and the demand is high- so long hard driving - there at their weakest.

In the future this too is going to become (is starting to be) a real issue for coops. Be good if there was a go to solution...

Regards

MM

We have thought for some time that the sonic welded joints have a tendency to stop working at elevated temperatures.

Update: After a great deal of research on fuel injectors in general, specs etc. I decided to change the injectors. I had established they were the cause of my problem but given the age of the vehicles I was not confident that spending money on second hand ebay injectors was a solution. I read this thread https://www.fiatcoupeclub.org/forum/ubbthreads.php?ubb=showflat&Number=653322 which established the real world flow rate of the standard injectors to be 360cc. I then made contact with a company asking their advice and they recommended these:

https://www.finjector.com/ev14_12_ohm_373cc_e_20_jetronic_o_o_61_mm_tot_78mm-p-137105-0

They obviously flow a little more at 3 bar but I figured it would be within limits. My concern was the impedance being 12 ohms but given what barnacle said and looking at a french forum where others had used 12 ohm injectors with success I went ahead and ordered. They supplied a flow matched set with printed sheet showing the static and dynamic flow rate and msec resolution from 8-15 volts.

Long story short; I installed without issue, ECU reset and immediate start settling into a perfect idle. Approx. 500 miles later, no sooty tail pipe, perfect starting hot and cold, plugs look perfect compared to sooty black before, mpg increase and the car pulls like a train. It has a narrow band lambda gauge fitted and all looks OK off and on boost. Not a cheap fix but it now runs like a new car.

Hope this might help someone in future

That's very interesting.

My plugs are sooty black as well and I was warned at last MOT about emissions being a borderline fail so I was thinking I'd either need to try changing the cat in the exhaust (not easy when the entire thing is welded together) or else the injectors.

Did you test if the 20 degree spay pattern was the same as the original Bosch injectors? It sounds about right from memory when I was cleaning the Bosch injectors but not sure if it's exactly the same. And the number of holes at the tip is very different, original Bosch only has 4 and these ones have 12... although maybe it doesn't really matter if they're all still spraying towards the intake valves OK.

My coupe has been off road since January but I'm tempted to try a set of these injectors and then take it for an MOT.

Hi Graham,

No I did not do a spray comparison before fitting, I knew the original spec was 20 degrees and took Bosch at their word on the new ones. There is a coding system for that type where A = thin spray C = cone spray and E = twin spray followed by the degrees between the two sprays, its listed as an E20 so I went for it. I remember seeing another spray pattern version of that injector listed there somewhere...

One issue I was concerned with was the potential for poor low engine speed running, but these modern injectors seem to of moved on a bit. The resolution or dead time at 12 volts is 1.4ms and at 13v 1.3ms and this has been born out with a perfect engine idle and pick up - I'm starting to sound like a Bosch salesman but the difference for me has been night and day.

If you do go for it be aware that they are approx 0.5 mm longer which means you need to apply a firm pressure to the fuel rail to get the mounting screws started, alternatively you could just elongate the holes a little but I did not find it necessary.

Guy

Thanks for this post Clanger,

This is really helpful. I'm guess the up shot of a new injector is that technology has moved on in what- nearly a quarter of a century and these new injectors I presume are likely better then the OEM from in the day. Or at least as good as the 25 year old OEM injectors which are starting to break down.

I'm keeping this link in favs!

Regards

MM

ohh and the website coverts into Eng-er-lish as well!

Bonus!

This is a great thread, I've learnt more about fuel injection in the last 10 posts than I have in the last 10 years.

Thank you Clanger, I’m certain many coupe owners will be grateful for the information you have passed on that will help keep the cars on the road.

Thanks for the info, doesn't sound like a major problem. I've already replaced the fuel rail bolts with normal hex bolts so that should make it even easier.

I've ordered a set of the injectors and will try to get some pics of the spray pattern of these + the original Bosch before fitting. May take a while as my garage is all taped off inside with plastic sheeting for spray painting so I can't access my coupe or tools at the moment.

I found that Finjector put up a Youtube of the injector spray pattern https://www.youtube.com/watch?v=SYxF4bi1tlE

Looks same to me except more atomized. What do you think?

Yes, I'm sure that's what Fiat would have used in the first place if they'd been available at the time.

I've bought a set, I don't need them, but you know how it goes! The link from Finland fell over if I tried to pay with Paypal, so I paid with a card, after the transaction went though I got a message that the freight wasn't enough and that my phone number wasn't recognised, so I cancelled the order and bought some from the US for a similar price. I got an email from the Finnish mob about my card refund, but it went to my spam folder and I accidentally deleted it. So I'll have to keep an eye on my card transactions and hope the refund goes through in the next day or two.

Awesomely helpful feedback post, thank you clanger

Thanks all for the appreciation. I have been helped out enormously in the past by people returning with a solution on forums and indeed for my Coupe by all the information on this great site.

@Grigio I'm sure you will get your money back, Marko seemed like a professional guy when I had contact with him, very responsive and fast to ship. Did you order the injector extenders and additional O rings too from the US supplier?

I'm not concerned about the card refund, he was up front about it, the refund email from his system turned up in my spam folder, but after I hit delete it's gone, and not to my deleted items folder. I didn't know I required the extra bits, that's what happens when fools rush in where angels fear to tread. Do you know what size the extenders are? I'd better track some down or I'll just end up with another impulse buy of shiny bits sitting on a shelf in the shed.

The Finjector page I linked to provides for the purchase of the injectors, adaptors and O rings as one packaged product for the price quoted plus VAT. If you set the page to english up on the top right and then move down the page you will see it says "This product contains the following items" it then lists the injectors, adaptors and O rings along with their part numbers.

Thanks Clanger, after having a look, doing some homework and cross referencing I've found a set of height extenders from a local mob that should get here before the injectors from the US. It would have been cheaper to source the whole lot from Marko, but at the time it fell in to the too hard basket.

So my length extenders turned up yesterday and I'm informed by Oz post that the injectors will turn up tomorrow. Show me a pair of 40IDFs and I'll rebuild them in my sleep, but I've never touched anything with injectors. Is there any sort of lubricant used on the o-rings before fitment? Any traps for new players I need to look out for?

Just use regular engine oil on the O-rings so that they don't snag on anything and they'll pop in smoothly.

Clanger, have you had an emissions test done since fitting the new injectors?

I had slightly black plugs and was warned at last MOT that emissions were borderline fail and something had to be done for this year. Fitted a set of these Finjector injectors + new spark plugs and although car is running fine, better throttle response, no smoke etc., took it for MOT today and it massively failed on emissions (on everything, CO, HC and lambda readings - WAY rich on lambda, nearly 20x over on CO), much worse than last year and it's only done a few hundred miles since then.

So not sure whether to re-fit the original Bosch injectors and try again (even if it fails, just to see the result) or assume that it's actually the oil rings that are dodgy and break/scrap it. Looking at the plugs again they're not that bad but it does maybe look more like oil contamination than soot.

If the rings are passing oil into the combustion chamber does it mean the fuel doesn't burn properly and you get very rich readings? Is that how it works with bad oil rings? Compression was fine when last tested a few 1000 miles ago and it still runs fine, yet all plugs are a bit black.

Here's one of the plugs... a bit black, but is that oil fouling or carbon from running way too rich?

^^ That was one of the new plugs that has done 4 miles, here's one of the old ones with a few 1000 miles on it :

Hi Graham,

No I have not had emissions tested yet, due next March. I've got a narrow band AFR meter fitted and I'm seeing it bounce back and forth at idle and on a steady throttle when warmed up. I would be surprised at it failing that badly given the Bosch EV14 resolution but obviously not count it out. Perhaps it could be linked to the impedance difference. I have read a lot of discussions going back a few years now where people have swapped out their old injectors for these without issue.

Your plug pics look like oil fouling to me - the glossy black sheen rather than mat sooty black which I was plagued with. Low compression thru worn rings could cause rich running but I would of thought you would of felt that and seen a low reading on the compression test. I guess the only way to be sure would be to swap back the injectors and re-test, have you got a friendly mot man?

Guy

edit, the new plug does not look so bad does it?

Just did a compression test and got 149-152 psi across all 5, so that's fine.

No, the new plug isn't so bad... it's actually running fine, no smoke or misfire so the problem isn't so bad other than the terrible emissions fail, haha.

Maybe just bad oil control rings on all 5?

I have a huge supply of spare parts so will try different injectors, airflow meter and ECU at least before scrapping it I guess.

The grey flaky build up looks like a burnt oil deposit. What's it like on oil? Is a hotter set of plugs an option? Although that won't help with emissions.

Graham have you got a spare lambda sensor to try? If you have an ACR you could check the lambda reading?

I've only done a few hundred miles in last year but it's not using much. Less than my last coupe over last few thousand miles anyway. It's not smoking so I don't think it's burning much oil, although apparently enough to kill the emissions. I thought about trying hotter plugs but they're not fouled enough to cause a misfire and yeah, it wouldn't help the emission anyway.

Dave - yeah I thought about that and checked last night. On the ACR4 the O2 reading was just stuck around 850mv (moving maybe a few mv occasionally). I had another lambda sensor from a box of random parts I bought, no idea if it was even working but tried it anyway and it gave similar results, but this time stuck around 760mv. So both reading constantly rich.I even tried pulling a vacuum hose off from rear of plenum which should make it go lean but O2 reading only dropped 5mv or so, so clearly something very wrong.

I did have that last NGK lambda sensor fail after only a few thousand miles so it's now on a genuine Bosch sensor... strange there's no movement from either sensor so maybe both these Bosch sensors are dead as well. I'll order a new Bosch sensor just to try it, but suspect it'll be stuck at rich as well.

You'd think if the sensor was stuck showing rich that the ECU would lean out in response, so was kinda hoping the sensor might be stuck showing lean causing the fuelling to go rich.

I replaced the ECU and airflow meter last night as well, with no difference... still just stuck on rich reading. I've got a spare fuel pressure regulator so will try that when the new lambda sensor arrives next week, also with the original Bosch injectors too. All other readings on the ACR4 looked fine... intake air temp, coolant temp, airflow, battery etc.

Is it really possible that a little oil passing the rings would cause fuelling to be stuck at very rich?

I don't think its an oil issue causing it. The issue existed before but seems to be exacerbated by the new Bosch injectors which do have the ability to provide lots more fuel if the fuel pressure is raised beyond 3 bar. Can you test the fuel pressure? It is a common factor and does not throw a code.

My understanding of the Lambda system is it only corrects within certain limits, could the sensor be reporting rich but it is so far rich the ECU has run out of compensation factor? There is a calculation for checking if the CO reading at the MOT corresponds to the Lambda reading and if it does the system is in closed loop and working;

Lambda value = (14.5-(CO% x 0.37))/ 14.6

Its accurate to within a very small margin, I checked it on my other car and it seems to work. Might be worth plugging your CO reading in and see if it corresponds.

Only other thing is coolant temp sender putting it on constant 'choke' but you've ruled that out.

I don't have anything to measure the fuel pressure but I have a spare fuel pressure regulator I can swap in to try. Maybe the regulator isn't dropping below 3 bar as it should with intake vacuum.

Yes there's a limited amount that the ECU can reduce fuelling... the ACR4 was showing injector timing down at about 2ms to 2.5ms , I'm not sure if that's as low as it can go though.

Your formula seems to near enough match the emissions test fail readings :
Fast Idle test : CO=3.95%, HC 135ppm, Lambda=0.904
2nd Fast idle test : CO=5.36%, HC 291ppm, Lambda=0.861

For a pass CO must be <0.3%, HC <200ppm and Lambda between 0.97 and 1.03

Those lambda readings aren't the same as what the ACR4 shows though, the diagnostics show the actual voltage reading (between 0 to 1v) from the sensor, That should be around 0.5v for perfect fuelling, above 0.5v is rich and below 0.5v is lean.

OK, some progress. It's the injectors!

I put the Bosch injectors back in and the lambda reading is now bouncing up and down between about 150mv and 850mv just as it should. Of course no guarantee it'll pass the emissions test but at least it's not running constantly super rich now. And pulling off the crankcase ventilation hose on back of plenum made it run lean on the O2 readings as you'd expect, whereas with the other injectors it just stayed constantly rich.

When I pulled out the fuel rail complete with the Finjector injectors I could smell the petrol just out of the intake manifold and off the injector tips, never had that with the Bosch injectors before.

Clanger, I'd get your emissions tested ASAP... my coupe felt OK with these injectors so you may not notice the over-fuelling, but if yours are doing the same as mine then it won't be doing the engine any good at all.

I'll contact Finjector and see if they'll take these back for a refund.

That's a difficult assumption, Graham - it's not the absolute voltage from a (narrow band) lambda sensor such as the coupe's, but the ratio of high to low *times* as the ECU tries to compensate in closed loop to keep the mix stoichiometric.

I'm no expert on the 20 ECU, but I'm pretty sure that if it were so far out as to be ten times rich it would be showing an injector light. Long shot - failed catalytic converter? If there's no change on the sensor voltage, or it's changing too slowly, the ECU shows an error.

Other things that might make things run rich:

- temperature is cold (thermostat fault) so ECU remains in start enrichment
- temperature sensor says its cold, even if not, same fault
- blocked air filter
- wrong fuel pressure
- air flow meter lying (and/or air leaks)
- throttle position sensor confused

Snag is, there are so many feedback loops it's hard to see where to start...

Neil

Posts crossed, Graham...

Neil

No probs, I appreciate the comments anyway.

For the 20v ECU it seems to only flag lambda sensor errors for short (over 1.099v) or open (below 0.0879v) circuit, or voltage stuck between 0.4v and 0.518v for more than 2.5 seconds. So apparently if it's stuck very rich but not into short circuit, or very lean but not into open circuit, it doesn't show an error.

I'm pleased you have a resolution Graham.

The situation you describe when taking out the new Bosch EV14's is exactly the same as I had with the original Bosch EV1's - they were dripping petrol when removed, however it passed the MOT cleanly with them last March!

As I said before, I've got a car that now starts and runs like a new motor with the EV14's, clean plugs and tail pipe, no petrol smells, the complete opposite of before. I just can't believe mine is running that rich.

I'm not going to be using it between now and March (roads too filthy) so will leave them in and see what result I get at the test.

I wonder if they possibly sent me the wrong injectors... does this calibration chart look the same as yours?

Yes, mine are just one point less across the board on the dynamic flow figure.

I still cannot see why you have a lambda reading that sticks voltage high or rich when you put them in and yet I see the AFR gauge (which I believe just reads the voltage straight off the lambda probe) bouncing around on tickover and constant throttle and going full rich on boost exactly as it did with the old EV1's

Graham, I'm also using the EV14's and as Clanger's position, it is running fine with no petrol smell and considerably less soot on the tailpipe. I will plug in the ACR and see what the lambda readings are for the sake of comparison.

My calibration chart has similar readings to yours with only 1-2ml variance between yours and mine.

I’ve checked my lambda readings and it’s swinging between 100mV and 700mV promptly...so would appear quite normal?

I got a reply from Finjector and it's not good...

They say the dynamic flow is bigger for the new injectors (0280158124) compared to the original Bosch injectors (0280150450) :

0280150450 q-dyn with 300 kPa, ti 2,5 ms (g/1000 Imp.) is 5,53
0280158124 q-dyn with 300 kPa, ti 2,5 ms (g/1000 Imp.) is 8,05

These new ones are flowing over 45% more than the original Bosch injectors, so it's no wonder it was running so rich.

They say the ECU needs to be remapped before using these new injectors and they won't accept a return because they've been used, even if only for 3 miles!

Does the Finjector link on 1st page go to the wrong injectors, or do you guys running them have a re-mapped ECU that handles the higher flow? Or have they changed the spec since you got them or something?

I am aware that they can definitely flow more than the standard EV1’s but I had the impression that the ECU would be controlling it’s output.

I am currently running the EV14’s with your Gtec2, Graham.
Even if they are flowing significantly more at a given opening time and pressure, still doesn’t quite answer why our lambda readings (with the EV14) are different.

I doubt Finjector changed the spec of the injectors as your purchase date is only 10 days or so before mine.

Without a remap, how will the ECU know that you have installed new higher flow injectors? Does the ECU actively try to change injector durations to control lambda? What else can it do? But maybe if the flow capability is so much more, maybe its outside the range that the ECU can change?

Are you sure you both have the identical same new injectors 0280158124?

Can you get a remap Graham, or can you produce a new Gtec3

I understood from the previous owner that my car is stock wrt changes to fueling maps etc.

It is important to restate that this is a Bosch injector, NOT Finjector, they are are a Bosch distributor. If Bosch chose to modify the parameters of the injector I firmly believe (having worked extensively with the Germans) they would simply create a new product i.e. 0280 xxx xxx.

As Kelv27, I think that although these injectors have the potential to flow a lot more fuel, a combination of improved injector resolution (or accuracy if one prefers) and the close loop adaptability of the FI system (I don't know the limits of this and as much as I try I can't find the detail) means that they do work providing everything else is functioning correctly. How can Kelv27 and I see a functioning closed loop?

For what its worth I think you have a wider underlying fueling problem Graham. The clue being your car was a marginal pass for emissions on last years MOT - mine passed cleanly even with the leaking old AV1's. I would even go as far to stick my neck out and say your old EV1 injectors are OK. Barnacle touched on it a few posts ago. What ever it is, its causing the EV1's to over fuel and the new EV14's to massively do so to the extent that closed loop cannot be attained.

Exactly.

If we accept what Finjector say that these new injectors flow 45% higher than the original ones then it's simply not possible for them to be a suitable replacement at "open loop" full throttle fuelling.

Even if somehow my coupe isn't able to adjust "closed loop" idle and part throttle fuelling as the 2 other coupes apparently are, the "open loop" full throttle fuelling is based only on preset maps (the lambda is ignored at full throttle) so couldn't possibly be OK without remapping the ECU to account for the extra fuel.



That doesn't make sense though. Either they are a suitable replacement for the standard injectors at "open loop" full throttle (where lambda readings are ignored and fuelling is based solely on preset maps), in which case they must flow a very similar or identical amount of fuel... or they flow a higher amount of fuel in which case they can't possibly be a suitable replacement for the standard injectors at "open loop" full throttle.They can't simultaneously be flowing more and the same at once, it has to be one or the other.



I think they are as well.



I don't think there's any evidence of that. I didn't get an emissions certificate last MOT so I have no idea what the actual figures were. It was tested cold though, so it could be as simple as that, as we know coupes like to be hot for an emissions test.

I won't know for sure until I take it back for an MOT with the standard injectors re-installed, which judging by the weather may be next spring, if I haven't broken or scrapped it by then.

To clarify, I was referring to when operating at higher fuel pressures i.e your FPR potentially being at fault. I was too subtle.

Yes, they'd flow more at higher pressure but so would the standard injectors.

Anyways, personally I think these injectors need an ECU re-map to work properly in the coupe, but if anyone wants to try them out drop me a PM and I'll sell them for half the price I paid for them, having done 3 miles.

Couple of points: any injector system is specified to work at a specific pressure; the job of the pressure regulator is to maintain the pressure at a fixed amount (2.5 bar rings a bell for the 20, but don't quote me!) above the current manifold pressure. The idea is that the injector then delivers the same amount of fuel for the same injector pulse length.

Second point is that the ECU does learn and adjusts its base values so that even the open-loop fuelling should be correct (i.e. it learns the offset during closed loop, but applies it throughout the range). That said, I'd be *very* surprised if it could cope with a 45% over-flow on either open or closed loop - fixing that will require a remap.

So what does a remap involve? Can the OEM ECU be reprogrammed or is it a replacement chip with custom settings burnt to it?

It will be a replacement chip. The EPROM holds both the software that the ECU executes and the maps that tell it how much fuel should be supplied at various standard settings, and those that tell it how to change.

I don't believe that there would be a need for new code - i.e. just the maps need to be changed - but it's rather dependent on how *little* the injectors will flow while still remaining controllable. From here, I'd have a word with Flea of this parish, but it's a bit of a trek from Tasmania!

Flea in the past has done both custom maps for tuned cars, and generic 'just make it a bit better' maps which will work with any coupe of the correct type.

Neil

Are these the little beggars:

https://www.ebay.co.uk/itm/Fiat-Lan...ol-Fuel-injector-0280150450/293175037970

Four is better than nothing....

One of them must have succumbed to the tear gas.

Seeing as someone was asking...

I re-fitted the standard Bosch injectors that had it (just) passing the MOT last year about 800 miles ago and it failed on emissions again. This time only 2x the max CO level though, so 10x better than with those other injectors where it was almost 20x over. So I suspect the other injectors over-fuelling so badly may have buggered the cat.

Not so easy to replace the cat as the exhaust system is a complete hand made custom job welded together from end to end in one piece, with sports cat part of the downpipe itself. So have dropped the entire thing, chopped it in half and fitted a standard downpipe along with a cheap (new) ebay cat. So now waiting for weather to improve and will try a 3rd (and probably final) attempt at an MOT.

I understood from a (former) coupe enthousiast that Bosch remanufactures "out of production" parts given enough parts are ordered.
http://www.bosch-classic.com/en/internet/bosch_classic/startseite/startpage.html

I have bought second hand injectors in the past to get them refurbished, the refurbisher indicated all were out of order. The second batch was better, so for my own coupe I have some in stock.

I'd be happy to participate in a group buy, but people will have to order substantial amounts and injectors are pricy.

@GrahamL: what's your plan now?

Another try at the MOT test and hopefully this time an emissions pass due to the brand new cat.

I think it'll most likely be fine now with the new cat on it but if not it'll be getting sold as a project (for someone else to fit a new engine) or broken for parts.

Sure you’ve checked this, but my 20vt used to just scrape emissions for years turns out there was a hairline crack in the exhaust manifold, if driven “vigorously” before the mot it would close up just enough to scrape through. After the crack became big enough to be heard and I replaced it the car has sailed through mot emissions tests. Just a thought.

I can't hear, see or smell any leak from around the manifold when it's cold but without removing the heatshield it's impossible to be 100% sure if it's OK.

An interesting possibility though, thanks. If it fails again at next MOT attempt then it would probably be worth checking the manifold properly before deciding to break/scrap it though.

I didn't get the full emissions fail report last time but was told it was just the CO that was the problem, whereas I think if there's an exhaust leak it causes the lambda reading to go high (lean)? Apparently a bad cat will cause a fail just on CO at up to 2x the max allowed, which is what I'm getting.

Finally some good news.

Back for MOT today with the new downpipe + cheap ebay cat and got a perfect pass on emissions and that was with the car sitting for 5 hours at the garage before the test so no great heat in the cat at all.

So, to summarise my experience with these new injectors :

1. Barely passed emissions test last year, 800 miles ago
2. Fitted these new injectors and failed emissions at 20x the CO limit (serious over-fuelling confirmed by ACR4 diagnostic)
3. Re-fitted standard injectors and failed emissions at 2x the CO limit
3. Fitted cheap (£50) new ebay cat and got perfect emissions pass, well below all limits

These Finjector injectors are confirmed by the manufacturer as flowing 45% more fuel than the standard Bosch injectors so even though they've apparently worked for some in this thread OK I'd be very careful as you might need a custom ECU re-map to use them safely. If you are intending a re-map along with bigger turbo etc. (aiming for 350~400BHP or so) I have a set of these injectors for sale at 1/2 new price, having done 4 miles.

Great result at last Graham - your coop still has a few of its nine lives left

^^ Haha, yeah, it's been on its "final warning" at least 4-5 times now.

Yay, a great result Graham, well done for persevering and your Coupe lives to fight another day. If I hadn't already got a set of injectors to go with my larger turbo I may well have bought yours, good luck with the sale.

Having driven the car abit more, thought I should update here on the latest developments.

Contrary to what I experienced and mentioned earlier, I can now confirm that my outcome mirrors that of GrahamL’s. Despite initially having no indication of the EV14’s over-fueling, the short term and long term fuel trim readings have now developed to be negatively off the scale...indicating that the ECU is most likely trying to compensate for the increased fuel delivery from the injectors.

I have since reverted back to the old, stock injectors and fuel trims have normalized. However, the car just doesn’t feel as good to drive despite the data showing that it should technically be more efficient. Perhaps the atomization just isn’t up to scratch compared to the newer EV14’s, but this prompted me to look further into the health of the old EV1’s.

All 3 sets that I have are showing excessive impedance. From new, they should be at 16 ohms but the ones I have are all over 20 ohms (some even as much as 30 to 40 ohms!). This would definitely be one, if not many, of the contributing factors to why it just doesn’t feel right. Given the age of the stock EV1’s, it’s pretty likely that most coupes out there would be running with similarly excessive impedance.

Looks like it’s back to square one!

A quick search brought up this seller on aliexpress (https://www.aliexpress.com/item/32961492447.html). Now, I would be reluctant to use injectors of unknown origin myself without testing them, even though they say they're tested. But, if they are not obtainable new now, perhaps it's a viable option...

PS, someone bought them from the same seller, but at a bit higher price (https://www.aliexpress.com/item/32845639786.html)

I’ve seen those..but unfortunately they are not new either.

Interesting! Where are you reading that from, is that something I've missed on the ACR4?

I hope your cat is OK.
(Otherwise we might need the services of these guys : https://www.imdb.com/title/tt11318602/ )

They were read via Multiecuscan which is much more detailed..being able to chart out graphs makes reading much easier too. My ACR now lives in the boot of the car and used for roadside reading only


Haha ironically I just completed watching this last night!

Hello
two years ago an injector broke down. I changed for bosh 0280 155 830 from volvo .(EV6, resistance 12.5Ohm)

with multiescan, I read the FRA, TRA, LAMBDA INTEGRATOR out of negative limit which meant that the ecu was trying to impoverish the mixture.

If you look on characteristics you will see that origin 0280150450 have same Q stat on 300Kpa (373ml/min) but in driving conditions, applying TI of 2.5msec, for 1000 pulses, 300kpa, origins flow 5.53gr, volvo 7.95gr. so 40% more.


The Kappa 20vt are using same reference that coupe.

The marea 20vt run with bosh EV1 0280150974 ( 5.7gr for 1000 pulses of 2.5 msec); the only ones that could be plug and play; I think learning can compensate

The lancia thesis 20vt run with bosh EV6 0280156056 (7gr for 1000 pulses of 2.5msec): but it is bosh me7.3.1 and not 2.10.4.

the difference comes from the reaction of the injector coil to open (call dead time)

I searched a long time and I found absolutely nothing plug and play with the same characteristics and still in production.

sorry for my english surely not perfect

Thanks for your information, after a lot of searching I have found the same. I'm taking another route with the EV14's

Your English is fine

The main problem is that whatever happens you have to re map the ECU.

I found in the motronic 2.10.4 dead time and now it works perfectly and I run with ethanol E85 or unlead petrol and parameters TRA or FRA stabilize around 0.

I m looking for "injector scale " in the map. If someone want to share the adresse, it would be fine .