Really Bad Vibrations

[neris]

I'm away at school and I'm home every weekend to work on my notch, and take care of the 94. I went home last weekend after the car was parked for a week and there is ridiculous amounts of shaking going on. The car is not missing, and it still accelerates at the normal rate. The motor is shaking uncontrollably causing the whole chassis to shake.
I thought it was just my exhaust missing a bolt, but even that wouldn't make the car shake so bad.
My idea is that it's the harmonic balancer, but I don't see the balancer going bad randomly and producing that much shakiness. The other theory is one of the motor mounts could have either broken entirely or just the bolts came out.
At a higher speed/rpm the shaking is reduced by a little, but it's still enough to feel it. The vibrations go through the entire car, even in park.

Any ideas? Thanks!

 

[mikey94gt]

check the harmonic balancer. if it wobbles alot, its definitely broken. common problem on higher mileage 5.0l engines.

 

[neris]

would it just happen just like that though? from very mild to extreme vibrations?

 

[mikey94gt]

it could, if you romp on it here and there. I had the one in my 88 completely seperate on the freeway, and I had to get towed. whoops.

 

[neris]

I see, thanks man!

 

[Matt94GT]

what about the mounts?

 

[neris]

I'm thinking of that too, I'm back at school so I don't have a chance to go outside and check everything right now. My dad & brother are going to look at it whenever they've got a free minute

 

[modo]

if it is the dampener stop running the motor. bearings will get wiped out pretty quickly

 

[neris]

yeah i stopped driving it after i felt it.

 

[mikey94gt]

Good dude. sounds like you know whats up too. Got pics of the cars? they look nice in the sig pic.

 

[neris]

my 94gt








my bro's 91gt (351w & d1sc)











and heres my notch in progress

 

[mikey94gt]

sweet cars bro!!! Love the D1sc 351w fox, im doing a similar build in my 94gt.

 

[neris]

thanks

hes trading the d1sc for a tt kit. twin m11 garret turbo's

 

[mikey94gt]

Wow. I wanna blower for the pretty much instant boost. its nice to have power like that for road racing.

 

[neris]

yeah
he's capped at 550 right now anyway cuz he needs 60lb injectors & a HUGE fuel pump. also untuned

 

[mikey94gt]

wow, nice!

 

[MikeF]

I am having problems with vibration also but i did have 2 ballancers go bad and after my last one(last weekend)I was thinking my bearing had gone also because i still have vibration but now it when car in under excelleration or decel.I also changed the tranny mount but not u-joints.they looked good with no slack.could it still be bad u-joint.its feels like that or flywheel.not trying to jack your space.

 

[mikey94gt]

Check your pilot bearing. I had bad vibes for a while, and had a known good balancer, and it ended up being the pilot bearing. they suck to replace tho. the grease trick works tho...