Very strange wobble relative to throttle position, and a function of speed

I have a 2001 legacy auto with 150k on it. It started doing a strange 'wobble' while I was driving it. The best way I can describe it is a wobble, feels almost exactly like a wheel imbalance, however it is only when I am on the throttle. I have to be pushing on the throttle more than 25%, So it CANNOT be a wheel bearing, wheel imbalance, or any tire vibrations. The harder I push on the throttle, the more severe the wobble is. It doesn't effect the steering wheel anymore than the rest of the car, that is, the car as a whole seems to shake, it has nothing to do with a CV axle. The wobble is also relative to speed, the faster I go, the faster (but not necessarily more severe) the wobble becomes.

 

The only thing I can think of is something on the ass end of the trans, or something in the differentials. It is not relative to what gear I am in, or what RPM the engine is at. I did the traditional front diff test: turn the wheel all the way and accelerate. The front diff did not scream one bit.

 

I tried plugging in the FWD fuse, to see if disengaging the rear drivetrain would stop the wobble, but the problem was still there.

 

Any and all thoughts are welcome

 

 

P.S. A CEL code popped up around the time the wobble started, P0340: Cam position sensor. I have gotten the part but will not be able to install it for 3 weeks, I am back at college and left the car resting in the driveway at home. I don't think that this is the problem, that sensor would not be relative to the speed of the car, it would be effected by engine RPMs

worn engine/tranny mounts maybe? just a guess.

Thats definitely a possibility, I didnt think of that. I would think itd be a tranny mount rather than an engine mount. Ill def take a look at them once I get home.

when it starts to wobble, put it in neutral. if it goes away, its in the trans..if it stays, its in the engine

Check for loose bolts on the wheels.

I had a wobble sensation and it turns out the wheel was loose. In contrast to your situation, the wobble (and sound) only occurred when I released the throttle.

 

Justin

hm.. I did try that. stood on the wrench for every bolt. Still does it.

 

I guess it could be a CV shaft. im running out of ideas

Rotate your tires from front to rear. Sounds crazy but I've experienced this more than once in my career and a shifted belt in a tire will do exactly what your describing.

I was asking my physics professor and he said to do the same exact thing. And they are cheap-all weather-made in china tires, so that could definitely be the problem. I will do that as soon as I get home in about a week.

 

Thanks!

 

Conrad

I have this same problem in my 03 with 100k miles. just got new tires today.

OK so I (not really me, my brother ) FINALLY figured it out. I had the CV axle replaced in the beginning of the summer. The part I got was some cheap made in china JUNK, only because im a poor college student. It turned out it was failing miserably and created a lot of play. While I was at school my bro replaced my CV shaft and the problem was solved.

 

Thanks to all!