My apologies in advance for the long post, but the issue is an odd one...

I drive a B6 (2004MY) S4 Avant with about 56,000 on the odometer. I had my car in for routine service last Wednesday and while it was there, I decided to have a few minor annoying things fixed as well - brake pads to stop the squeeking, the 12V power adaptors in both the front and hatch and the center console top. On Saturday, I fill up with 93 at a gas station that I've never gone to before.

Fast forward to Sunday. I drive to the Mall - about 3 miles from my house, spend about 30 minutes shopping then return and start my car. It stalls after idling for about a second. I'm thinking that's odd, I've never had that happen before and I try to restart the car. It wont turn over. I try a couple more times. The starter sounds fine and the battery is providing the crank - just to make sure I had a Sears tech come out and check the battery, its good. I let the car cool for a bit, still no go. I call Audi Roadside. The driver of the flatbed tries to start the car and no dice! Its towed back to my dealer (Don Rosen).

Okay, so Monday - The tech at Don Rosen tries to start my car and varoom! no problemo! WTF!?!? They check the computer, no codes. They try to re-create the conditions that I had - car still starts. I get the car back yesterday and no problems. Nice thing - no charges for anything.

So what the hell happened on Sunday? The tech at Don Rosen said that maybe I wasn't pushing the clutch in enough. I don't believe that because I've been driving this car since March of 2008 with no problems. Also the Driver of the tow truck couldn't start it. Anybody experience anything like this? Any ideas?

 

could be a rpm crank sensor starting to go bad.

 

what sucks is most techs (including me) will tell you that you have to get the problem to happen more frequently, and the problem has to be there while were trying to diagnose it.. that way we can see if theres no spark, no fuel and that everything is mechanically sound. i had similar symtoms with my b5 s4. i would get in the car, crank and crank and after 10 minutes or so it would fire up and act like nothing was wrong or had happened. it turned out to be bad gas. if you fill up with 93 oct. you have to realize thats the least used fuel out there that you can buy at the station. so the fuel sits longer, giving it more of a chance to draw in impurities and such from the tank. ... just an idea..

 

Thanks guys. I'll call the dealer to ask if they checked the RPM crank sensor. Although, it is likely that they did not since the problem refused to show itself again.

If it is bad gas, do you think that a fuel additive - e.g. octane booster or water remover would work? (I think the biggest issue with fuel that has been around for a while is water absorption.)

Anyways, this all has me a bit nervous as I am driving to visit my brother in Cleveland and I would be seriously upset if my car STB'd somewhere along I-80 in jubumfuk PA.

 

It was the fuel pump. My car STB'd on the Ohio Turnpike about 40 miles from my destination. That was fun... or something else that starts with an "fu"

 

wow, that would have been my next guess. sorry it left you stranded.

 

Good thing this car is still under warranty. Aside from getting more good practice at getting a disabled vehicle off the highway, I've only been inconvienced by several hours over this. My car probably has cost Audi a pretty penny since I've had an oil leak in April that killed my car in Pittsburgh, then I had to have it towed on Aug 30th and again on Sept 2nd. They're paying for my rental this time too.

Unfortunately, its also going to cost them a repeat customer. I'm getting rid of this car, much to my disappointment, when my warranty runs up at the end of March. Its sad because I cannot think of a car I'd rather have (that is not also an Audi) than this one. Nothing approaches it in terms of performance and style - in my book. Of course, this is trumped because I cannot afford to have a car that will both cost me a fortune to repair and is not reliable.