I have a question for anybody who can answer it. My 1990 gsx galant is making a vibrating noise when the rpms go over 3 or 4 in 1-3 gear. someone told me it could be the manifold...(exhaust or intake manifold i have no idea which). And i'm wondering if this could be the problem. once i hit 4 and 5 gear the car run great but below that it just runs like crap. If anybody can answer my question please let me know.

jcue

Might be the exhaust. Mine does that too sometimes. I think the bolts on the downpipe may be loose. I also have the exact same model and year. Mine has a Thermal-R catback:bigthumb:

I've had mine for only a few months and it's seems like a really good car. The car run awsome on the highway but the thing is once it starts hitting high rpms it makes a loud vibrating noise.. other than that the car is great. I plan to fix up the car once I starting making money. How long have you had you Galant? Are they pretty realiable cars?

In another 4 1/2 months I'll have had it for a year. They seem to be just as reliable as any other DSM , which means they will last forever and then bite you in the ass. I drove mine to NY from Colorado , and back. About 4000 highway miles at 90+ mph with no incidents. Mine also had the transfer-case recall done and a new T-belt when I bought it.
Do you mean it vibrates at certain mph speeds , or only beyond certain rpm's , there is a big difference between the two .:wink:

it vibrates at certain rpms

Originally posted by jcuellar
it vibrates at certain rpms

Sounds like some weird harmonics. T-belt done recently? Might want to check the motor mounts , make sure they are all secure. Do you get this same vibration revving it in neutral , or only in gear? Might actually be a drivetrain vibration. Those can get real complicated to find.

it makes that sound running or in neutral as long as the rpms are the sound is right along with it

Could be anything from a warped flywheel to a bent pulley. Or possibly one of the balance shafts is a touch off. The front BS runs on a belt , so that would be the likely suspect. Are you planning on doing any modifications?