I have just had the cav GSi mot'd and it passed but the CO reading was about 3.5%
the car is a 1990 GSi with a CAT and a lamda sensor.
The mot man said it could be the airmass meter causing the problem as the car hasn't been used for about 4 years.
I thought cars with cats were only suppost to have about 0.5% CO.
Any ideas what is could be.
Could this also be the cause of the revs seeming to hunt when at idle. Also if I rev the car then press the clutch the revs drop right down to 200 or 300 rpms then return to idle at about 800rpm.
no fault codes is good cos theres nothing major wrong..but BAD cos there obviously is summat wrong! make sure the bulb is working! hehe
try carb cleaning out the inlet, breather piping and ICV
dont clean the AFM, i think the heated wire ones can get damaged
oh, also buy the obligatory new ecu temp sensor. cant hurt.
did you reoil the ICV, might explain the revs dipping
yeah you can test the sensor, ask andyk for the resistance across the pins at different temps
weird ready doesnt always show as a fault, but yeah chances are its summat mechanical. maybe a dead cat?
i never really bothered about emissions tho TBH, i always had a garage that turned a blind eye and 3.5% isnt bad (what year is the cav BTW?)
you dont need the cat and it wasnt a cat emissions test, so the limit will have been 3.5% i guess (or summat it is higher)
cat cars do tend to have very low emissions tho, as you say the post 1992 test is limited to 0.5%
dont worry about it too much then, i thought you meant it passed on everything but emissions