So I did the search and couldnt find anything that coincided with these specific symptons....

So, a little history...i got the car in march, 89 5-speed s4 with 125k...
a few months ago it started to have an in idle problem, it would die after a few minutes, but only when the engine was cold. I did the WD40 trick, and it ran like a champ...didn't stall for a long time. The car always started right up on the first crank.

One day about a month ago, for the first time it wouldn't start at all. it would crank, but no fire... luckily i was parked on a hill and i popped the clutch to get home....after that it started fine but the rough idling started again. I thought maybe it was some bad gas because it smelled a bit rich, and then the problem disappeared. two weeks later I drove from S.F. to L.A. and back and the car ran fine, started fine, idled fine, etc...

This week was rough...on monday it wouldnt start at all...I waited an hour, went back still no fire. I dont use the car every day, so I let it sit...Went out this morning, still no start. I disconnected the battery for a few minutes to reset the obd, and she cranked right up....didnt sound too bad, but wasnt exactly a smooth idle, and the engine had some louder than usual ticking sound....I took her for a little drive, at first there was a lag in power around 2500 rpm....at one point the engine slumped for jsut a second, and the abs light flashed.....but then it would drive strong again...It also started right up after I ran a few errands...this continued throughout the day until I was in traffic and suddenly the engine started surging....very rough, as if it was running out of gas....I pulled to the side, and it died on the spot...i was on a uphill so i freaked a little, started it up, and kept surging, but i had to get off the main road...i found a parking spot and left it....luckily i was close to work, so i walked...on the way home, it started right up...started driving home and it would slump but not as violenlty, then die for a second, and then come back on as i was rolling (this is in the city, so it was just inbetween stop signs....i wouldnt try this at anything over 20 mph).....it did this several times, then ran fine....by the time i got home ten minutes later it was running fine again, even idling fairly well....

so what could be wrong? electrical or fuel lines are my assumptions.... by the way every time the engine stalls, the ABS light comes on...is this normal? thanks for any input...sorry for the mini novel of a post....

 

You dont mention what maintenance has been done since March?

Right off the top I'd be looking at fuel pressure (the fuel pump may be gone) and doing a full diag on the LH ecu that controls the fuel injection. If these checkout then look at the electrical side........crank position sensor.

This would be after all maintenance.

 

ah, sorry....first thing done was TB inspection, changed oil and all filters, checked levels, everything is good....also had to replace two fuses...they were too high a voltage (thanks to PO) among these were the diagnostic and hatch relay...

Its due for a major service, and in the next month Im going to take it in (maybe sooner, given the state of things)...it would be nice to have something specific to have on the docket while shes under the knife

 

"Novel" is better than too little info. A post with "Idles weird and dies" is pretty hard to diagnose. It sure sounds like the ISV is part of the (multiple?) problem. The WD 40 is at best temporary and some better heads recommend you do not repeat more than once or twice.

Also sounds like spark problems. Have you cleaned all grounds? Check coil wires and coil grounds for corrosion?

 

I recently had a similar issue on my 89 A/T, after about eight months of sleuthing it turned out to be the crank position sensor, the three pronged connector was in pieces.