2003 A6 3L Quattro. There is an intermittent problem (gradually getting more often, now about 30%) when I turn the key to switch off the engine it continues to run until I take my foot off the brake. Naturally when I take it to the dealer it works perfectly. The service manager is supposed to be trying to find out if AoA know anything about this but after 4 weeks he still has no idea of the cause. Has anyone out there heard of this type of problem or have any idea what might be causing it. My main concern is that this changes from a not stopping problem to a not Starting problem at the most inconvenient time. Thanks to anyone with info.[&:]

 

Wow that odd ive never heard of anything like that

So if you dont have you foot on the brake the car will shut off like normal

 

Yes, as long as foot is on brake, engine just keeps on running. Take foot off brake and it stops immediately!

 

Really i cant help you out on this one

And if the dealer cant recreate the problem they cant do anything

 

It sounds like your car is dieseling. I would check the idle speed and timing, check for vacuum leaks (which could explain why the brakes have something to do with it), and the cooling system because a hot running motor could cause it to after-run.

 

The engine runs perfectly, idles nicely and steady at 750. No overheating. Its not after run from overheating. When you turn off with key, and engine doesn't stop, all electrics work normally, radio, a/c, lights, it's as though you had not turned key. Idleing doesn't change. Electric don't change, so I assume it is still getting a spark and therefore not dieseling. What other indications would there be of a vacuum leak? When you take foot off the brake it stops instantly, just like a regular stop with the key. The car just had it's 50000 mile service about 500 miles before this started. Could this be a corrupt computer chip which controls transmission, brake, and key switch for starting/stopping? Is there such a chip?[&:]
Thanks for the input guys.

 

Can you still rev the engine

 

I haven't tried to rev engine after switch off, but I will next time which should be in the next couple of days.

 

there are such problems? OMG. by the way, why Jap cars doesnt give this kinda problems?

 

why do you think my other car is Jap. But the Audi is much more fun to drive.