HARD shaking

[Emoney8924]

hey guys, i recently just got a very hard annoying shaking in the car.. I had put on some u.d pulleys, and it started to shake, i dont know maybe i interrupted the harmonic dampner.. i cant shake it though... doesnt feel loose on my hand. i dont know if there is a way to tell that that is bad. I start up the car, and from idle to about 2k it shakes the hell out of the car. I dont know what it is, the car is an auto, ive crawled under the car and tried to shake the driveshaft, i thought i might be a bad u-joint... but then again i dont think that would make sense if the car isnt moving either... it will do it with the car moving or not moving.. PLEASE help, i dont really want to buy parts if i dont need them. thanks for ur help guys!

oh yea i also swapped back in the stock pulleys.. still shakes..

 

[urban96]

make sure all the pulleys are on all the way

 

[Black95GTS]

Did you pull codes? Bet you got one even if the Check Engine light is not on. Sounds like a bad plug/plug wire though.

Mine did that... ran around all day checking everything with a volt meter. Then, remembering I drove through a puddle earlier I wrote a thread and got some good advice to pull the dizzy cap off and check to see if water got in there.

Sure enough, I just held a blow drier up to the dizzy for 10 minutes and found the cracked cap. Good excuse for MSD upgrade as well...

Adam

 

[Emoney8924]

did that too, torqued them all down to spec

 

[Emoney8924]

havent checked the dizzy yet, would that cause it to shake that bad though, like when i start it up it shakes so bad the panels inside the car rattle around.. and when i try to drive it up to 2k, it shakes HORRIBLY, sounds like the car is going to fall apart..

 

[Synned]

Is it a misfire? If you are driving does the RPMS jump like its skipping or is it smooth?

 

[urban96]

on the balencer inspect it to see if theres any rubber sticking out, thats the easiest way to tell if its gone south


i think parts stores sell a OEM one for ~50

 

[AznStanger3v]

its the balancer. there is rubber sticking out the back im assuming. it is a rotating balance so improper distribution of weight will throw it off.

 

[HISSIN50]

I like all the ideas here. Adam and I are in synch tonight as a miss was my first thought. One cylinder missing would clear up with RPM but the car would feel a bit gutless.

The balancer is possible too. Look for cracked elastomer or timing that walked from where you last set it. They tend to wobble when the elastomer goes south.

If you run it long enough to pull codes, Run a cylinder balance test (it's part of the code retrieval process). It'll tell you if a cylinder is missing - no muss no fuss. You just let it do it's thing.

Good luck.

 

[The Green GT]

The balancer wont always have rubber sticking out. Mine has so little sticking out I couldnt see it while it was on the car. But I took it off ans looked at my new one and saw that it had rotated 90*

 

[MI95Cobra]

try sarting your car and looking at the balancer....if you don't see rubber you'll see if it is really shaking bad....when my balancer went out on my 92 gt, no rubber was sticking out and when i had it running i looked under the hood to see if it was my motor mounts or what...and you could see the balancer shaking so bad i thought it was going to fall off....

 

[The Green GT]

An easy way to see if the balancer is bad is to check the timing. Ig the balancer spun the the timing marks will be WAY off.

 

[Emoney8924]

the car will run smooth so its def. not a miss fire... i started the car and looked at the balancer and it looks like it is shaking but its hard to tell cuz the whole motor is shaking too.

i dont think its the motor mounts cuz i checked those and they still seem firm.

 

[HISSIN50]

A 5.0L with a misfire is capable of running smooth enough to not necessarily feel the misfire.

You've been given some very good advice with things to check if you choose to do them. THere's not a lot folks from a keyboard can do otherwise to help.

Good luck.

 

[final5-0]

I've been following your thread and you got several good things to try.

Seems to me you had to disturb the hb ...twice ... now.

Since the oem hb is a known problem issue and all the more so as the miles rack up.

That would most likely be the prob and all the more so since you've swapped its pulley twice.

Grady