Hi all, I just got a 1987 S4 Turbo II it has 110,000 miles. I love it but when it has sat overnight or for several hours when you crank it up it won't idle. It starts great but for the first 5 or 6 times you crank it the car won't take any gas and it just dies, after those 5 or 6 times it will take gas but if you give it too much of take your foot off the pedal it will die again. When it gets warmed up it runs like a champ. I also has a fairly bad exhaust leak at the manifold and/or turbo I don't know if these problems are related. The previous owner also made it sothat the secondary intakes are open all the time. I've tried turning the BAC screw and i didn't notice a difference so i unpluged the BAC and the car died so i think the BAC works? I also turned the variable resitor to maximum rich and i think tht might have helped it slightly but not sure. I haven't got around to looking at the Trottle BOdy setting becuase i didn't know the best way to take off the intercooler( i assume you have to drain it?). The previous owner said the commpression was at 90. Any answers or reaconmindations would be greatly appreciated. Sorry for the lenghty post. thanks

 

Yes, the bac has been shown to work.

The intercooler is just a air to air radiator. Just loosen the two clamps on the large hoses and the two small hoses. Then remove the four bolts that hold it in place. Please remove a battery terminal so you don't accidentaly touch the alternator post and blow your main fuse.

Turning the variable resistor in a full clockwise direction will add fue. (only at idle), so it seems you have too much air in the idle system right now (added fuel made it run better).\

http://www.teamfc3s.org/info/articles/idle.html

 

so does the opened secondaries have anything to do with it?

 

no more ideas?

 

the extra air in the system may be cause by a vacuum leak...check all vac hoses, and any gaskets...the TeamFC3S article should be your bible...