ihfree

Driving over a mtn pass yesterday,my s6 started to stumble and buck.I pulled over and opened the hood,nothing visibly wrong but a strong sulphur smell. The smell dissipated and i continued to drive.The car lugged over the pass,i got passed by a minivan,when i got into town, the car seemed to be normal. I accelerated from a stoplight didnt seem to be full boost,lacking power,drove home and parked.I have not started her up this morning. Any help or insight will be appreciated Fuel Filter,Sparks,Cat????

JPQuattro

My old 95 A6 did the same thing when the cat broke up and clogged the pipe.

donalds4

I've been chasing down a problem for 2 weeks now,same symptoms, but no sulphuric smell.The car idles fine, takes the throttle fine if done moderately.If you punch it, it bucks or stumbles, until you ease up,then all is fine.Got under the car, tapped the cats, and they " rumbled"..So, block cats for me.Thanks for the diagnose,JP Quattro

ihfree

had to hollow out the cats for now ,replacing soon thanks

Bill the Cat

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