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924IRL · Joined: 30 Aug 2005 Posts: 8

Hi again. As the weather has started to get colder here I've noticed that, say 4 out of 5 times my car is incredibly difficult to start in the morning. When it eventually starts it only idles at about 250rpm for about a minute. Then it's fine. Also, if I restart the engine about hour after driving it it runs really rough for a couple of seconds. It's like it needs to clear itself out. It's had new plugs, distributor cap, rotor arm etc. Could this be the cold start valve I've heard about? Thanks.

Smoothie · Posted: Sat Oct 08, 2005 9:11 am Post subject:

Could be a few different things, but my first suspect would be the AAV (auxiliary air valve). If it starts and warms-up better by holding down the throttle a bit, it's time to take a look at the AAV.
_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

924IRL · Joined: 30 Aug 2005 Posts: 8

Thanks Smoothie! That's exactly what I have to do before I leave my house every morning. It usually takes about 1 minute to start the car. Then I have to hold the accelerator pedal at around 1500 revs for about 1 minute. Then it's fine. Would the AAV also be a likely culprit for the rough running when the engine is restarted after short periods?

Smoothie · Posted: Sat Oct 08, 2005 9:30 am Post subject:

If you get the engine good and warm, stop it, start again in say 5-15 minutes and it's hard to start, then that's more likely the warm/hot start problem. The operator work-around is similar though - hold the pedal down to the floor while cranking and let up as soon as it starts.

OK - I see you said it happens after sitting an hour, so that wouldn't be the hot start problem. Yes, it could also be caused by a faulty AAV and again if holding the pedal down some smooths it out 'til warm, the AAV's still your prime suspect.
_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

924IRL · Joined: 30 Aug 2005 Posts: 8

I'll have the AAV checked. It always starts first time after an hour. It's just really rough for about ten seconds. It's kind of embarrassing when passers by start staring at it! I know it's electronic ignition but it almost sounds like when the points have closed up and the car starts spluttering really bad.