1997 mk3 golf 16v idle problem and co2 level to high

[vento dan]

hi hope some one can help me plz cos im puzzled i have just got my self a 1997 golf gti 16v and i have just put it through its mot and it failed the co2 is to high and the idleing is all over the place and in the morning it wont start when cold with out me being gental on the throtle and once warm it starts fine but the idleing is still all over the place so plz help me it would b a great hlp thanks dan

[Crasher]

Start by getting it read for fault codes. The most common problem I see on these engines is failure of the ECU relay, it is at position 3 on the relay plate (upper main row, third from the left) and has the number 30 printed on top. On a couple of occasions I have had poorly G3 16v’s come in that have been driving their owners crazy and I have found this relay to be missing.

[vento dan]

thanks 4 that i have changed the relay and still no good i have just got a code reader so i will try that. the funny thing is that i have changed the idle controle valve and when i un plug it the car will idle fine so im stuck again any more tips will be a grate help cheers dan

[Crasher]

Start with a code read, print the codes out, clear any codes and then run it again. Drive it for a few days and then re-scan to see what comes back and these codes you can trust. I think that your problem may be a faulty coolant temperature sender.

[vento dan]

yer thats wat i was thinking but just at a loss im a 8v man realy the problem is that i can not run the car as it has no mot because it keeps failing on the emissions high co but thanks for your help cheersdan

[vento dan]

hi i have pluged my car in to a code reader to day and it come back as the water temp sensor and the speed crank sensor so i will keep every one posted so hopfully the car will now pass its mot cheers for your help dan

[Crasher]

I thought the coolant temp sender may come up and the crank speed sensor G28 is a common failure.

[vento dan]

right i have now changed all the parts that the code reader and took the car back for mot and the co is still to high but when i fiddeled with the idle control valve so the car could suck some air in the cars co went down so when i pluged the code reader back in it come up with the thrrotel positioning switch and now the car runs at 2000 rpm all the time this car is driving me mad now do i change the idle control valve as well even tho it does not come up on the code reader can any one help plz thank dan

[Crasher]

What do you mean fiddled with the idle control valve? You can’t do anything to it. What codes are you getting now?

[vento dan]

What do you mean fiddled with the idle control valve? You can’t do anything to it. What codes are you getting now?

bye puling it out off the rubber bung so it could suck some more air in throug the inlet manifold the only code im geting now is the throtle position switch thnk for your help dan