99 gst engine shaking..

[willie97]

Hey guys. Trying to figure something out. I just bought this car, and when I drive it the car shakes. It only shakes when I give it gas.. when I let off the gas the shaking stops and it is coming from the front. If I get on it real hard I cant notice it as much, but when i drive it normal it shakes the front end pretty good... any ideas???

 

[770eclipse]

Is it in the front end or in the engine? If it is in the front end it is probably the ball joints or wheel bearings. If it is in the engine talk to the place or person you bought it from and ask them if they had just changed the timing belt. If they have it is that the balance shafts are not in time. Let me know if this helps.

 

[snakeyes711]

Drive axles are probably shot. Look at the boots see if they got rips in them.

 

[luv2rallye]

Also check engine/tranny mounts.

 

[willie97]

great info. Thanks Guys. The timing belt and head gasket were both replaced. I pulled it all apart and re-checked the timing and it was in time. I can re-check it all again I suppose. I also checked the motor and tranny mounts and they all look fine. Maybe ill just replace them to be safe anyways and I will also check the drive axles. I looked once and didnt see and tears, but I didnt look real close.

 

[dannyd97gst]

Also check engine/tranny mounts.

I just put some Energy Suspension motor mount poly inserts in my 97 and it shakes like a 1 legged washing machine at idle but before this the engine did vibrate under light acceleration.

 

[Harriz801]

You can't check timing on balance shafts without removing the timing belt. At least not on the oil pump gear. If this is something to do with timing then you probably shouldn't drive it until its figured out.

Does it sound like its missing?

"If I get on it real hard" - when you do this do you feel it cut out during acceleration?

Are their any mods done to the car to be hitting fuel cut?

 

[jdd1231]

Will it shake when its just sitting still if you step on it?

 

[snakeyes711]

I just put some Energy Suspension motor mount poly inserts in my 97 and it shakes like a 1 legged washing machine at idle but before this the engine did vibrate under light acceleration.

Yeah def. check if its got racing mounts first. If they are poly or hard mounts then you know it. If they are still factory, inspect them for damage. A blown engine mount or tranny mount will in turn blow your driveshafts.

 

[willie97]

You can't check timing on balance shafts without removing the timing belt. At least not on the oil pump gear. If this is something to do with timing then you probably shouldn't drive it until its figured out.

Does it sound like its missing?

"If I get on it real hard" - when you do this do you feel it cut out during acceleration?

Are their any mods done to the car to be hitting fuel cut?

No, it doesnt sound like its missing or anything. Drives great, builds boost now, and all is good. The only mods are a hard upper pipe and dejon intake and HKS bov recirc'd. BTW, if I didnt mention this, I fixed the missing/bucking problems. It was the plugs. I just got another set of new ones and gapped them at .028 and now its fine.

Now, this isnt a vibration so much as a shaking. I know what vibration from hard mounts feels like. Besides, these are stock mounts and all appear to be in good working order. I did fix some major boost leaks that I found and that seemed to help the shaking a little bit. Only things I can narrow it down to are either something with those damned balance shafts, or I jsut have alot of really bad leaks... I am going to check the leaks and redo all the lines myself. If that doesnt fix it then I would assume its the shafts.