Pierburg carb probs

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Thu 3 Jul 2003 00:28
Pierburg carb probs - peter101
Hi
Can anyone please help me!? I have just fitted a new waxstat to my 1.6 golf (2E2) carb which I bought from VW. Since I fitted it the car would idle at 600rpm (hot), and when cold at 1000 rpm. I adjusted the idle speed by turning the screw at the 3-4 point unit, and have managed to get the car to idle at 900rpm. The problem is that the car doesnt seem to go onto choke at all even though the butterfly flap closes, etc. In other words it does not seem to idle when cold at any revs higher then 1000 rpm. Despite this, the car runs perfectly hot and cold!!(Very smooth now when cold)! Is this the way the car should have run all along. I mean, I know its summer and it is warmer, but before I changed the waxstat, when I first started the car it would rev at 2000 rpm, and then slow to 1000 rpm.
I looked at the pin on the new and old waxstat, and the pin on the new stat is 1cm from its base when cold, whereas the pin on the old one is only 3mm from its base.

When I spoke to VWs and asked them if waxstats are ever faulty new, they said that in order to return the part, I would have to book the car in for an hours labour (GBP 88)!! to check that it is the part that is faulty and not anything else.

I am worried that the car wont run on choke in the winter at all considering the low cold idle speed!

can anyone advise me on whether this is normal or should i take the risk and argue with vw about faulty parts?

Thanks for any help!!!

Peter Cohen
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Thu 3 Jul 2003 09:17
Pierburg carb probs - Adam Going (Tune-Up)
Hi Peter,

There is an adjustment for cold start fast-idle rpm. It is likely that this had been backed right off to compensate for the tired old waxstat, and now requires resetting.

Engine stone (overnight)cold. Remove air filter assembly, and blank off the vaccuum pipe that was supplying vac to air intake system. As you view it from front of vehicle, just to the right of the waxstat and slightly below it you should see a small allen-head bolt (5mm I think), head pointing to nearside of vehicle. Loosen this slightly and you can move one of the two halfs of the fast idle cam relative to the other. Start the engine and with a screwdriver push the slightly pointed half that is nearest the cam cover downwards, and the revs should increase. When you have achieved satisfactory rpm pinch the allen bolt up again. Fully tightening it will move the fast idle cam fully off and engine may stall, so check rpm by restarting. Alternatively, you adjust it bit-by-bit with engine off and check rpm on re-start.

HTH, Adam
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Fri 4 Jul 2003 11:54
Pierburg carb probs - Drew20
The cold idle can be adjusted as Adam says, I would say that your revs are not causing any running problems so why change them.
My golf runs at about 1100 when cold and 850 when hot

if you slaken the bolt Adam mentions you can adjust the idle speed by moving anything attached to the throttle butterfly. I use the hot idle lever (the bit that rests on the 3/4 point thingy when hot)
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