Alot of engine vibration

[GstStang]

For the last week or so I've had my engine start shaking alot! I've analyzed all the signs:
•It shakes only while in gear and acceleration. No vibration if I rev in neutral
•Vibration increases as I change gear and accelerate (i'm guessing ### of the gearing)
•The vibration is slower than as if a piston was misfiring
•No visible signs of anything unbalanced: No unbalanced tires or bent axel n harmonic balancer is fine
•It's NOT a misfire ### I've had plenty of those

My guess is that it's the flywheel is getting warped, last time I changed the cluch I was told that it would be the last time I can use it. I also drive my car pretty hard every now n then I just wanted other opinions, clutches n flywheels

 

[zachyd23]

If it was something in the engine wouldn't it shake anytime I raise the RPM? No shaking when in neutral or out of any gear. I've been thinking it's drivetrain related but I can't figure out what and I don't really have the money to be guessing. The axels, clutch or flywheel have been my best guess because when I shift gears all those are disengaged and no vibration occurs

The rate at which it vibrates is what leads me to think it might be the cluch or flywheel because it's not a very fast vibration but it is powerful.

When the engine shakes during driving/acceleration, have you noticed any power loss vs when it wasn't shaking?

 

[GstStang]

I can't really feel any power at 2300 rpm. I can't go any higher in rpms because it shakes real hard

 

[dsmlover07]

MMM interesting in the 15 years or so in the dsm world never hard that happen before.

 

[solson1041]

I'm not about to act like I know any more than the fine people on this forum. But to my brain, I think it's worth noting that the engine will behave differently under load. I know when I had a bad boost leak, The car would idle fine, but jump and lurch when I tried to drive it.

You said you know this isn't missing, so I'll take your word for it, but before doing any MAJOR repairs, it might be worth it to investigate that in my book. I know the symptoms you listed fit what I had. It doesn't seem like it would be an axle or flywheel to me, because it's related to RPM, not speed, so there goes axle in my book, and a flywheel would probably shake in neutral as well right?

I had a slow and powerful vibration, but again, I'm not trying to insult your intelligence if you don't think it could possibly be missing/boostleak/richness issues.

Good luck, hope I might have helped.

 

[dsm44130]

ide swap rims and tires and see what happens.tires are tight but maybe they arent seated right ,are they after market rims that maybe have a larger center hub so they sit ob-longed till you tighten the bolts evenly to bring it center?

 

[GstStang]

I ordered the engine mount by the timing belt just in case, it seemed like it might need replacing.

solson1041: Hey that's a good idea, I'll check. I forgot that it is similar to what's happening.

dsm44130: I have the stock 97+ GSX rims. I've had them on since I bought the car 9 yrs ago. I'll check for any bends on the inside of the rim

 

[GstStang]

if it only shakes under acceleration then it has to be one of the axles .

You were right Lou98GSX! The passenger side axel was the problem, the CV joint had lost some bearings so that's what caused the vibration. I bought a new axel n installed it yesterday and it runs great now Thanks for all the ideas guys, now after checking all the stuff I checked I know the rest of the car is cool Lol

 

[supermario300hp]

I had the same problem on my first dsm. It happened after i switched to my winter rims... the car would shake like crazy and i could go more than 3k rpm. soon as i switched back to my other rims the car went back to normal. im pretty sure its your problem.or it could be the mounts.either way at least its not too expensive. Im also pretty sure its not boostleak or your flywheel.

 

[josh1095]

well, im in the same boat now. just got car running and have a shake at around 55 mph. might check half shafts too. gonna swap rims front to back first. glad u got your problem solved.
rereading through the posts, though, i still dont see why it was only happening under acceleration. that is really weird. the half shafts are rotating whether your under throttle, coasting or just whenever your driving. good info nonetheless. thanks

 

[GstStang]

well, im in the same boat now. just got car running and have a shake at around 55 mph. might check half shafts too. gonna swap rims front to back first. glad u got your problem solved.
rereading through the posts, though, i still dont see why it was only happening under acceleration. that is really weird. the half shafts are rotating whether your under throttle, coasting or just whenever your driving. good info nonetheless. thanks

I think it would happen because the axels rotate seperate from the engine and are smaller in diameter so only minimal vibration would be felt. When the clutch engages to the flywheel the rotational force is increased and so is the vibration.

 

[josh1095]

^^^^^
makes sense, thank you

 

[TallestHERETIC]

I've actually come across this probelm, but it was in my 420A.

Have you changed your coil by any chance? My engine vibrated so hard I thought the engine was going to drop out the bay!

I had a defective coil. You could actually see the sparks all over it while the engine was at idle. Bought a brand new one and it no more vibration.

 

[GstStang]

I Resolved my problem, it ended up being the passenger side axel.

 

[98gstbrad]

did this happen right after you put the new clutch on?

 

[GstStang]

did this happen right after you put the new clutch on?

No, it was just with age

did this happen right after you put the new clutch on?

No, it was just worn by age. I never chafed them since I have had the car, almost 9yrs

 

[josh1095]

mine was solved easily: rotate tires. the ones were in the front are out of balance i guess.
these tires have been sitting for nearly a year now. this build has taken a ridiculous amount of time. theyre mismatched too. sorry to hijack.