Club 80-90 Forums

I have a 2.1 petrol. Digifant MV I guess.

It has been starting ok. Idling at 800 then increasing to 12 to 1300 when warm. I tried some of the suggestions on wiki to cure this and three people have looked at it but it wasn't too much of a bother so I left it.

Well now it won't idle when warm and struggles under load. It's kicking out black smoke as well. The local T25 Guru is stumped. He's replaced the Mass Airflow Sensor. He's also replaced the fuel filter and cleaned the tank. As far as we can tell there are no bad connections or air-leaks.

He says it has a Lambda sensor but isn't sure if that would cause it. Could it be that? How do I test the ECU.

Or probably more importantly. Is there a T25 Guru anywhere near Shepton Mallet. I think it needs a fresh mind.

Checked the temp 2 sender? The one that tells the ecu the temp of the coolant and a lot cheaper than the AFM.
Vital for correct cold start etc
ECU probably thinks its in the arctic all the time, so permanently overfuelling.

disconnect the lambda signal wire and insulate ECU side on connection so no stray signal to ecu and try running it, may be a little down on power but should run and not black smoke, and you can then check to see what the output from the lambda is, measure the voltage earth, 2V scale should cycle from 0.3-o.8V ish but I bet it is reading low and not cycling high which is failed lambda

Thanks

Getting a new Temp sender. We'll try this first. I'll let you know how we got on this Friday.

The new Temp stat didn't change anything. Checking the wiring again and Lambda sensor output next.