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spellmaster
30-09-2006, 08:34 PM
My A4 faild its MOT today on a susspension arm (now sorted) and Co2 emissions :aargh4: being a bit over regs 4.18 (against the regulation max 3.00)

Was told that it could possably be the oil condtion but its recently been changed, or the fact that i am now doing very short journeys and its abit clogged up.

Is it possible that all it needs is a good oild itallian tune up? if so ill get my heavyest boots on :biglaugh:

ceeijd
02-10-2006, 03:09 PM
Im having a similar issue.

After fixing the suspension arm and other parts, im left with the car failing its emissions with the CO sitting at ~0.6%.

I have fitted new plugs and an air filter [it was really clogged up]

I have now ran 3x fuel treatments through it and really hammered it on the motorway before taking it straight into the test station and hooking it straight up to the machine, but it is still failing at ~0.55% CO.

This time I tried unhooking the Air flow meter and got the garage to run the test again, at idle the specs were far out but at fast idle it was still failing at ~0.66% CO.

Right now im thinking the AFM could be at fault, as surely is should have failed by a bigger margin when unplugged? I am considering getting a new one [AFM] ordered today and also getting an oil change/flush done on it.

Does anyone have an opinion?

Thanks,

Ceeijd.

spellmaster
02-10-2006, 05:55 PM
Done some more digging since my last post. I have identified a few things that may have contributed to a rich mixture.

the plastic pipe work to the throttle body was weaping oil, so if oil could excape then so can air. and as its after the air has been meaterd the wrong mixture would then be in the chamber leading to a slightly rich mix. So a simple cleaning and tightening of clips was all that was required there.

Another thing worth checing is the crank case breather pipe work as i had to replace that lot 12months ago after it all disintergrated again leading to rich running. Its in a tricky place under the inlet manifold.

Also there is a check valve in the break servo line wich seemed to be letting air pass both ways, i swaped this out with a spare.

however not haveing a Co tester i have no idea if this has made any difference:zx11: , but the car feels more responsive.

spellmaster
04-10-2006, 10:05 PM
:biglaugh: passed, just that loose inlet hose did the trick!:D

adamss24
04-10-2006, 10:11 PM
glad you back on the road again... drive safelly !