I love MOT time. Please help diagnose my emissions problem...
Failed due to 6.3% CO, 145ppm HC and 0.843 Lambda. Previous results were more like 0.2% CO and other values similarly low so there is clearly a problem.
My cat warning light has been on, but would a failed cat make such high readings given that this car should be able to pass without a cat at all? Could the cat warning light be caused by the O2 sensor failing?
I am overdue for new plugs and dizzy cap/rotor so will be changing them in the next few days, I doubt they would cause these readings though...
I have tested the voltage between E1 and Tf1 in the diag port and get 0.04v when cold, 2.5-3.5v when warm. It was pitch black out when I did this and I'm not sure if it was fluctuating.
Sometimes boost is limited to just over half but I had put this down to the low air temps lately - performance otherwise seems fine. There are no fault codes stored.
I am going to try to diagnose the O2 sensor using http://www.mr2.com/TEXT/MkII_O2_Sensor.html tomorrow.
I can't afford to go replacing bits that don't need doing so any further advice would be appreciated...
Emissions again
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Re: Emissions again
first things first, what car do you have?
Re: Emissions again
Sorry, I meant to put that in somewhere
1993 Rev2 Turbo
The o2 sensor voltage doesn't fluctuate btw. Checked it again today and I was getting 3.5v at idle and dropped to less than 0.1v when engine speed increased past a certain point. I was on my own though so still haven't done the proper diagnostic procedure.
1993 Rev2 Turbo
The o2 sensor voltage doesn't fluctuate btw. Checked it again today and I was getting 3.5v at idle and dropped to less than 0.1v when engine speed increased past a certain point. I was on my own though so still haven't done the proper diagnostic procedure.
Re: Emissions again
http://www.imoc.co.uk/forums/viewtopic. ... hlight=mot
This will help you pass the mot in the meantime while you search for the culprit.
Effectively Unclip the pipe.
This will help you pass the mot in the meantime while you search for the culprit.
Effectively Unclip the pipe.
Re: Emissions again
Thanks, I would try that but since I don't have emissions testing equipment at home I have no way of knowing what does and doesn't work!
A friend of a friend runs a garage so perhaps I can get some time on a tester before and after removing the pipe...
A friend of a friend runs a garage so perhaps I can get some time on a tester before and after removing the pipe...