misfiring?

 

the check engine light is not flashing, and i just had misfiring diagnosed and treated around 2 months ago. so i do know what that feels like.

would changing the oil in both the transmission/transaxle differential and the rear diff make a difference too? or could it just be residual kenetic energy being discharged through the drivetrain onto bad engine & tranny mounts?

 

maybe a dying fuel pump or clogged fuel filter?

 

A problem I had with a '99 4Runner that exhibited the bucking turned out to be bad spark plug wires. Maybe the same?

 

I know this is an old thread, but it most accurately describes my issues.. Any fixes? I've got a 99 A6 avant with tiptronic. Under light load, under 2k rpm, I have a knock and hesitation I can feel in the cabin that feels like it might be related to tranny issue. Happens more when the car is warmed up. I can reproduce it pretty easily by accelerating to 50 mph, coasting, then getting lightly back on the gas in either auto or tip mode. Any help appreciated.

 

Sounds like a misfire, my chrystler van does the same thing. Will buck at 2k and after I hit. 3k it's fine. Check the plugs gap check the wires. Check the ignition system.

 

Thanks for the reply. I've noticed the problem primarily when the car is warmed up. I tried to reproduce the problem a few times while it was cold and couldn't. I wonder if changing the tranny fluid to a thicker one could help.. Atf4 ? Any thoughts? It wouldn't be cheap to do it right and not just flush it.