Buying '93 S4
 

Another lurker converted...

I've finally gotten pretty serious about buying a UrS4. I've been researching 'em for a bit and they seam to be a pretty well rounded car.

I would've kept doing my research and been on my merry way if I didn't take a friend of a friend's for a test drive today. First time I had both seen and driven this S4 and it was quite a pleasant surprise. The car is a pristine black on black '93 with 216k km's (140k miles?). The interior and exterior are completely flawless, you can tell the car was well taken care of. The car has a complete service history since new. It's been a one owner car up until my friend's buddy bought it a couple months ago and it was dealer maintained for the extent of it's life time. Now, what's the downside to this beauty? Well, there's only really one... the ECU seams to be running in "limp" mode. There is zero boost at any rpm in any gear. As well, the chap whose selling it suspects one cylinder isn't firing correctly. If that's the case, it's an "easy" fix. If not, I'll be asking some more questions here before too long.

All in all, just looking for some general ownership/purchasing advice on what appears to be a near perfect example of a UrS4. I'll try and get pictures soon... though that will undoubtedly take a few days.

Lastly, any idea what a car like this is worth without it's one major problem (pristine, black on black, 140k miles, all records, one owner, no nicks/scratches, perfect leather, all electrics work, 100% stock)?

Thanks in advance to all that give me a hand.

Corey

where are you located? I would assume...
 

canada seeing as how your talking km's. I would summon someone up there that may be local to go and look at it with ya...

Be careful
 

I can't think of any simple problem that would result in NO boost. Are you sure it made no boost at all? If so the car would be very lethargic. If there's no boost at all it could need a new turbo. That's actually not all that expensive of a proposition, but with a dead turbo you can't determine the condition of the really expensive bits (i.e. the rest of the engine).

If it was making 6 or 7 PSI, then there may be a simple fix for that. The car actually feels pretty decent (though not fast) at that kind of boost level. Around 6 PSI is what you would get from mechanical regulation of boost via the wastegate spring when the ECU can't or won't modulate the wastegate frequency valve (WGFV). The ECU can't reduce boost below that level, so 0 PSI is a bigger problem than the ECU.

It might be making some, but it might feel like none.
 

I'd check the moisture trap first.

The boost problem is not related to the cylinder firing. $3500.
 

If you are serious about the car, agree to a price if you get it sorted. Take the car and see if you or someone can fix the problem(s). If yes, you have your deal, if no, give the car back and eat any attempted repair costs.
But "as is" with an unknown "firing problem" and no boost, the most I would pay is $3500 if the car is otherwise clean.

2nd.

Where in Canada are you? I suspect you're talking about a "93" Elmwood Canadian (more)
 

car that is actually a 92 spec car (i.e. it has a boost gauge). The problem is likely a little hose under the black 4 x 14 x 3 cover on the fire wall. The OEM hose clamp is crap and comes off the moisture trap. 5 minute $ 0.60 fix good for 12 psi (over the wastegate 6 psi).

I can hook you up with people in Canada if you tell me where you are located.

And US$3500 is not realistic. (Too low)

IMHO

Dave F. Vancouver

Thanks all for the help... read on.
 

I appreciate all of you chipping in your opinions on what the problem could be.

To describe the problem a little more (based on what I was told and what I know)... About two months ago when the current owner of the car was purchasing it, he took it for a test drive. In 3rd gear when he mashed the throttle he noticed a bit of a hesitation halfway through the rpm's, but besides that he was getting full boost. The shady sales guy said "oh that's nothing" and the problem got worse from there.

I agree, it may be possible for there to be boost, but it really is hard to tell. The car didn't have much zip to it and there was a slight vibration at the right RPMs in 3rd. I didn't notice it as much in the other gears, but it felt like one cylinder wasn't firing correctly. The car still picked up and ran alright, but nothing more. I've been driving an old 140hp pontiac parisienne around (read white trash winter beater boat) and I'd stick bets on it being able to keep up to this S4. If the car was making 6 psi and all 5 cylinders were firing correctly I'd imagine it'd have a bit more power than what it does... but it's really hard to say.

As it stands right now, the car is getting inspected the beginning of this week if we can't figure what it'd be by then. The purchase of the car is conditional on the problem being fixed (assuming it's an inexpensive fix)... no deal otherwise. If the problem is something big, the chap will just keep the car, sell his other Audi and stick the money into the S4.

As an aside, I'm located in Edmonton, AB, Canada. If there's any local Audi-nuts that think they could help, I'd appreciate it. Thanks again guys.

Corey

No boost gauge and has carbon fiber trim
 

Suspected actual '93. Can anyone verify?

Corey

Here's what I think the problems are:
 

But first a disclaimer:
While these are very common issues, there is the potential for less likely but much more severe issues to exhibit the same systoms. Do not buy the car hoping that I am right. According to my wife, this is rarely the case.

Anyway:
The skip is a coil pack, if not a coil pack then the POS, but coil pack is most likely.

The lack of boost is the vacuum hose blown off the moisture trap under the plastic cover against the firewall.