Anyone ever figure out the Vibration issue on 2.4

[Alero 2 Envy]

Ok I got a 1999 2.4 Auto with about 120,xxx miles. Done the major tune up which included new:
AC Delco plugs, boots, coil wire, and coils (didnt change coil housing)
Fuel filter
Air filter
FP regulator
Front O2 sensor
New muffler
IAC
TPS
No vac leak found
No CEL (ever)

Car runs great when I 1st start her but the minute it warms up it turns into a damn vibrator. Now it only vibrates in forward gears, if I put it into park or reverse it goes away. Im thinking motor mounts but just curious before I start dropping money on guesses has anyone ever figured out this common issue with these 2.4's (clogged cat, convertor) ????

[Alero 2 Envy]

Well I guess no one has figured it out then....

I will share some info, I changed front and rear engine mounts and it purrs like a kitten now. No vibration at all, even with the A/C full blast. Who would have thought 2 $16 mounts would have fixed my issue I have been having for over 2 years.

[01silveralero]

i have no vibration problem with my 2.4

[whiterider00]

very oddly enough i just came here to post a question about the exact same thing. in N and P its fine but in drive it shakes, and makes noise, at least for me. i wish i knew what it was cud its really annoying, and i just throw it in N at stop lights. if anyone knows i wud, actually im sure WE wud appreciate some help. thanks.

[meadus101]

Mine bounces around like a stripper. How hard is doing the motor mounts?

[AlbinoMonkeyRat]

Originally Posted by meadus101

Mine bounces around like a stripper. How hard is doing the motor mounts?

well, judging from the name, these are the parts that keep the motor on the frame (sue me) so my guess is you would need a hoist, just to lift the engine a bit to replace the mounts. so...if you have the right tools, it's an easy job...but if not...SOL.

[whiterider00]

the weird thing, is it doesnt do it all the time. and is accompianied by a very annoying sound, almost like something is loose under the hood. ive checked,and cudnt find anything loose, so i dont know, maybe its just something im gonna have to live with.

[Alero 2 Envy]

Mine would shake and make noise also like the prop rod was loose. But it took about 45mins to do the front mount and about 3 1/2 hours for the rear which was a pain in the ass. There is a bolt on the back one that is right between the rack & pinion that takes forever to get out because of no space. Oh and the bolts are 18mm and might be a good idea to have a rachet wrench in that size also. I simply raised the car on stands and used a jack to support the engine since there are 3 other mounts holding it when you do 1 at a time. I used a small peice of sqaure cut 2x4 and wrapped a towl around it and put it on the jack which went under the engine being careful not to put it under an obvious weak spot that would collapse like in the middle of the oil pan. I did not break anything or hurt anything so you must be careful if you do it this way as it can cause problems if your not careful. Oh and one more tip, wait till your car is cooled down or cold. Also change both even though you might think its only one. Have fun !

[SittinOnChrome]

my 2.4 has some vibration and sounds when I first start it up goes away after engine is warm, its just been that way since Ive owned it.

[CharleyO99Alero]

***

No vibration problems with mine. Perhaps someone already changed the motor mounts before I bought it.


***

[cherrington17]

Originally Posted by meadus101

Mine bounces around like a stripper. How hard is doing the motor mounts?

might also be your struts.... depends on when its bouncing..

[whiterider00]

Originally Posted by cherrington17

might also be your struts.... depends on when its bouncing..

wud u be able to elaborate on that? i just got new struts, but one of the front mounts may be bad. think this cud be the problem?

[DOHC_tuner]

I think I know what it is. I have the same problem. It doesnt vibrate when in park or reverse....well when I was putting my LD9 back in the bay I noticed my front tranny mount was no good....but I didnt replace it just yet..I can almost 100 percent bet its that tranny mount.

[whiterider00]

so far that makes the most sense...if it only does it when in gear, it shud have something to do with the tranny.

[ndottaylor]

So i read all the replies on here and wanted to ask a quick question... what causes the car to vibrate a lot when the A/C is on? It does more when in drive and very noticable when sitting at a red light or just stopped and still i drive or reverse. This only happens when the a/c is on. Any clue??

[[ion] C2]

more load on the engine, has to spin the compressor