audi 3A engine

[jamiecoysh]

hi all i have a 1989 2.0 8v audi 80 with the 3A engine and im having a problem where every now and then when i pull up at lights or sometimes im heading downhill in for example 4th gear with my foot off the gas and i dip the clutch like pull up at lights and the idle will be 1000 rpm, when its normally about 750. If i leave it and continue driving the engine becomes really snatchy when taking my foot off the gas to slow down. \if i switch it off and back on again its fine untill the next time. I recently changed the isv and when it did this problem with replacement isv, insted of idle being at 1000 steady, it would rev up and down fast between 900 and 1300 rpm when it started to play up.

just wondered if anyone has come across this prob maybe with the equivilent golf engine

cheers

[The Mighty Elvi]

Oh...where to start..


 

[The Mighty Elvi]

Try asking in an Audi forum...


 

[AudiA8Quattro]

What is injection system is fitted?

[X4MGS]

Try the S2 Forum; http://www.s2forum.com/

My S2 Had a similar issue and I replaced the MFTS (Multi Function Temp Sender) And cleaned all the contacts on the MAF & doused it in WD40... Just an Idea...

[clipperjay]

Does it have a micro switch on the TB if it does check it if it clicks okay?

[Diamond Hell]

Does it have a micro switch on the TB if it does check it if it clicks okay?

This and also IIRC there may well be an idle adjustment screw on the throttlebody.  This may have been wound up to compensate for a knackered ISV.

You also need to check all the inlet pipes for vacuum leaks - an unlit blowtorch is your friend - take it up and down the pipes slowly (outside is probably best  ).  If you find a vacuum leak, the engine will race on the gas.

[AudiA8Quattro]

+2 to the microswitch. I had this problem on a passat 2.0 16v with the 9A lump, it wouldn't idle, when i restarted all was fine, a new switch cured the problem.

[jamiecoysh]

hi all thanks for your replies

ill try and answer all the replies that have been listed 1stly ive already tried the audi forums but havent had much luck with them. the injection system is the type that uses the metering head ( think its a cis or something lol ) its the golf 2.0 8v gti engine effectivly just mounted round the wrong way lol. I was advised against playing with the idle air screw by the garage i use as the engine runs spot on and say hyperthically it was to cure this problem could strt a new set of running problems. I was leaning towards the idle switch myself. Does any one have any links to or pics of what it looks like and is it available to buy new or is it a new throttle body. Cheers

[jamiecoysh]

this is a link to the throttle body that it uses

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=280786157299&fromMakeTrack=true&ssPageName=VIP:watchlink:top:en

can i buy just the switch new (and where from) if it uses one!

and are they hard to fit?