MAF Sensor voltages

I hope that someone can help me with MAF sensor voltages.
I have an initial rough idle and no acceleration after about 3000 rpm with misfire.
I suspect the MAF as the injectors are new and I think that the coil packs are OK (all of the spark plugs are the same colour; slight green tint on the tip, but black soot around the screw base, so running hot and overfuling I think).
My MAF is reading 0.18 V with no airflow, and around 0.8 V at idle. Are those readings correct? Information that I've found on-line tells me these should be 1 V and 2.5 V respectively.
Thanks for any advice!

Just disconnect MAF meter and take it for a spin. If it goes like a rocket you know the MAF meter is at fault.

Thanks OnlyItalian. That was a bit too obvious for me!
I tried disconnecting the MAF just now but it runs much worse. I also disconnected the lambda sensor (at different times) and this also makes the car run much worse!
I'm stuck for what to try next.
The ICV is clean and I know it is working as the software that I use had a test routine for it, and I can see it opening and closing on command.
I'm thinking fuel starvation or a vacuum leek.
I've already replaced the FPR and have a fuel pump on order.
Can anyone give me advice? The car is starting but not immediately as it used to, idles roughly (even stalling) until warm and then is fine at idle. I get no acceleration above around 3000 rpm.
It's a MY2000 20VT Plus.