Hopped in my car this morning to leave a friends house, and all of a sudden i got on the throttle to accelerate, and i felt what seemed to be a nasty miss in the engine, a very bad chugging vibration, i immediately got off of it...

go to ease my way back into the throttle, same thing! I immediately thought optispark (eventhough i just put a new one in) and put the clutch in to rev it up a little, maybe see if i can hear a miss, and she's purrin' like a kitten, no misses. *scratches head*

The vibration is there when the car is in neutral, but not as bad as when the car is trying to accelerate. It feels like the thing is going to shake apart with even a hair of acceleration, so i limped her home at 10mph, neutral whenever possible.

What is going on??? I just had an SLP billet flywheel installed around 3 weeks ago and it's been fine so far (fingers crossed). The SPEC stage 2 clutch is a little over a year old, and i havent' had any problems with that either.

This came on so sudden, i'm baffled... the only thing i can think of is the flywheel/pressure plate coming loose?

I need this car to be fixed asap, as i need it for work... ANY ideas would be VERY greatly appreciated!!

 

There was another thread similar to this one in here earlier titled "tell me why." There might be some info in there. I would say like I did in the other thread, it might be the pilot bearing on the back of the crank. If you just had a new flywheel put in, it's possible that the bearing was damaged when the trans was put back in. It could be possible that the flywheel is not balanced correctly, but I have had personal experience with a damaged bearing. I had vibrations under load and when the car was in neutral and revved. I thought it was the flywheel but it ended up being the bearing being damaged when we put the trans back in. Replaced the bearing and the vibration was gone. Hope this helps. Good luck!

 

Hmm, sounds like a place to start. Did your vibration come on all of a sudden like mine, or did it accrue over time?

In the meantime, i'll search for that thread.

 

If I remember correctly, it came on all of a sudden once we put the trans back in. We put a new clutch in the car and we must have damaged the bearing when we put the trans back in because it started happening right after that. We thought it was the stock flywheel possibly being warped that was causing it. So I put a SPEC billet flywheel in it and it was still vibrating. Then we thought the new flywheel might have been out of balance. Even a couple mechanics I had sit in the car thought it was probably the flywheel. So I was tired of taking the trans out in my garage 3 times within a month so I took it to a shop to see if they could figure it out. He called me a couple days later and showed me the bearing that had been damaged. New bearing and the problem was gone. Your car sounds like it's doing a very similar thing so I wouldn't be suprised if this was your problem. Good luck. Keep us posted if you figure it out.

Brian

 

It's funny you should say that your mechanics thought it was a warped flywheel causing a vibration, as mine said the same thing, hence the SLP billet wheel. When the stocker came out, it was fine.

If i remember correctly, the SPEC clutch i put in came with a new copper bearing...

Thanks for the advice, i'll look into getting it replaced.

Any suggestions for a part, or will a new GM part suffice?

 

No problem man. Hopefully I was able to help you out. As far as the bearing goes, I just got a new one from a GM dealer. I think it was $15. Good luck! Hope it works out for ya and you can get rid of that damn vibration. I know it drove me crazy trying to get it figured out!

Brian

 

It really sounds like a burnt plug wire more than anything to me. Remeber it will miss more when the car is under load.

 

you're correct rootster, i've got a "random cylinder misfire", and checked all my wires, but they're good. I'm going back into her today and double checking all the plugs.