I know this is FD forum but thought it might crossover as a problem bc of the engines, Car is S4 NA, AND Started the car up and was shaking horribly on starting sometimes it does it sometimes it doesn't so I have it some gas kinda pushed past it settled down after a couple secs like usual idled fine drove it down the road fine started acting wonky about halfway down the street going around 60 kinda hesitated a bit and dropped down so I let off the gas kinda still felt that feeling went to the light to turn around and I hear this loud *** slap behind my car and I was like oh **** min you my car has never backfired or anything did a uturn limped it home checked engine looked visibly and sounded visibly sound checked oil looked good no fumes or smoke coming out of the exhaust no smoke from engine not visible leaks no fluids

 

Do a compression test before going further. That's typical symptoms of a broken apex seal. If compression is fine then start troubleshooting.

Also, why not post in the 2nd gen forum?

Dale

 

His keyboard may not have an option for the 2nd gen forum. It already seems to be missing the period key so who knows?

I agree on the compression test though, I'd also check the plugs for ***** and giggles.

 

I posted in 2nd gen forums as well just wanted a wider spectrum of info because like I said could be a overall issue with all gens just did a compression test not to long ago read 85 on all 3 facings which is fsm spec and 95 on trailing all 3 and cmjust out fresh NGK plugs in about 4 weeks ago so legit brand new.

 

Had a similar issue not too long ago, ended up being a bad injector. So I did the only sensible thing and upgraded the entire fuel system.

 

Appriciate the insight my plan of action is checking compression once again just changed plugs and everything gonna check plug wires, and then move onto vac and air then move to fuel, and fuel pressure regulator and injectors!

 

On an FD, the vacuum line popping off the MAP sensor will cause this limp mode situation. Not sure if FC’s have a MAP though.