unstable idling and rough starts

my 99 2.8 has trouble starting once in a while. it feels like it doesn't want to catch and then it idles real high. other times it starts normal but idles high. I can not reproduce it nor can I predict it. I have had 3
or 4 mechanics look at it but they couldn't find anything wrong. when the computer is scanned nothing shows up. Anyone experience this? I'm starting to think its the computer. If it is will a mod chip rectify the issues?
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have you changed the battery or disconnected it recently? it may need the throttle body re calibrating,
Steve.
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"jprusso" wrote

Have you tried cleaning the throttle body?
Pete
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i have had the throttle body cleaned 3 or four times. this happens very speradically. audi service department says there's nothing wrong.
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j, OK, so you have an Audi.............. If it's a 5k/100/200, I can tell you it can be vacuum leaks, injector leaks, temperature sensor problems, vapour lock, bad gas, fuel pressure problems, check valve leaks, etc. etc. etc. Try: www.sjmautotechnik.com Cheers! Steve Sears 1987 Audi 5kTQ 1980 Audi 5k 1962 and '64 Auto Union DKW Junior deLuxes (SPAM Blocker NOTE: Remove SHOES to reply)

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"Steve Sears" wrote

Steve,
I guess you didn't catch the beginning of his thread. It looks like he's got a '99 2.8, which I'm guessing would be an A4 or A6.
Cheers,
Pete
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A4 2.8 quatro
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