vibration when accelerating

[obthomas]

Vibration is in the seat, firewall, car. The steering is solid and does not vibrate. Suspension parts are all OEM except struts are B6 not B4.
When I get to third gear about 50 MPH and give it gas I get what feels like an engine miss at 3000 rpm and goes away at 4000 rpm. I can do the same thing in 4th, 5th, and 6th. Of course the car is going faster in the higher gears. I have convinced myself its not an engine miss. No CEL.

[Qingdao]

So it dies off at different RPM ranges... now we have a clue.

I still think it could be CV axles, but if you are feeling it under rpm changes then its probably in the engine somewhere.

If it was me I'd find a quiet stretch of highway. Take the belt off and get it up to 80mph. See if your issues are gone.
^^just because that's easier than doing anything CV axle related.


I'd be willing to bet the reason you don't feel it in 1st through 4th is cause its such a low gearing.

[KRAM36]

Originally Posted by obthomas

Vibration is in the seat, firewall, car. The steering is solid and does not vibrate. Suspension parts are all OEM except struts are B6 not B4.
When I get to third gear about 50 MPH and give it gas I get what feels like an engine miss at 3000 rpm and goes away at 4000 rpm. I can do the same thing in 4th, 5th, and 6th. Of course the car is going faster in the higher gears. I have convinced myself its not an engine miss. No CEL.

Hook up the Durametric and take the car for a drive and check for cylinder misfires.

[The Radium King]

Originally Posted by KRAM36

Hook up the Durametric and take the car for a drive and check for cylinder misfires.

this - misfires don't always cel. if it feels like an engine miss then it may be a miss. also, try clutch in vs out of gear and load the engine (get it hot before hand, then go to wide open throttle) and see if you get the behavior without the transmission engaged.