weird shaking

RJ93SS · Post by **RJ93SS** » Sun Aug 23, 2009 7:21 pm

I noticed this when i got on it the other day. while accelrating, the whole car wobbles, or shakes now. it feels very weird. it's very noticeable. my boost gauge that sits loose on my dash bounces around side to side.

it's like having really sticky tires and a grooved road in the shape of a million s's

wtf

i'm going to have a look at it sometime today, where do i start?

suba · Post by **suba** » Sun Aug 23, 2009 7:52 pm

Is the shaking only while accelerating, or during other times as well? Does it happen while turning? Are there any clunks or other sounds that have appeared recently?

RJ93SS · Post by **RJ93SS** » Sun Aug 23, 2009 9:25 pm

seems to be more when accelarating, cv's are a few months old,
wrx struts as in my sig
havnt noticed it during turning

gijonas · Post by **gijonas** » Sun Aug 23, 2009 10:10 pm

Loose wheel? lol.

suba · Post by **suba** » Mon Aug 24, 2009 3:09 am

Couldn't hurt to check the lug nuts, I have had odd vibrations before and discovered a lug nut or two had loosened up.

RJ93SS · Post by **RJ93SS** » Mon Aug 24, 2009 5:21 am

i finally got to go for a drive after a very busy day. i must say, the car only shakes upon acceleration. as soon as i let off the gas, it stops. therefore, my thoughts lead towards a motor mount broken and my engine lifting. i dont tknow, i could be way off.

while idling, i hit the throttle from under the hood and the engine didnt seem to lift an more than usual. maybe a busted tranny mount?

im doubting a loose lugnut as it would do it on decel too. i slotted my struts for more camber, but the camber looks good. bad caster or bad toe cause i bent something? i could see that causing a problem. but i havent hit anything, just drove it hard.

the only thing i recently did was regap my plugs now that im running more boost, which i should have done back when i started running more boost almost a year ago. what a nice improvement.

im really hoping my front diff isnt wacked out.

ericem · Post by **ericem** » Mon Aug 24, 2009 5:51 am

With my car did the EXACT same thing. Turned out to be a bad axle. I did my tires, alignment, brakes, struts. Turned out it was just my stupid axle!!! Do a tight right turn hit the gas liek 1/2 throttle see if it clicks then try left. If left clicks then left axle, if right well ya lol. Even if there is no click it could develop soon. My car was clicking without a torn boot.

RJ93SS · Post by **RJ93SS** » Mon Aug 24, 2009 5:31 pm

axels are brand new as of 3-4 months ago

Post by **Legacy777** » Mon Aug 24, 2009 6:46 pm

Where'd you get them? Just because they're brand new doesn't mean squat.

http://bbs.legacycentral.org/viewtopic.php?t=40105

RJ93SS · Post by **RJ93SS** » Mon Aug 24, 2009 7:38 pm

they are altrom, apparently the best and closest to japanese replacement parts you can find in canada. theyre not ur cheap local parts store brand. and theyre brand new, not rebuilt.
the nuts were torqued to spec and punched.

ericem, what failed on your axel?

ericem · Post by **ericem** » Mon Aug 24, 2009 10:46 pm

not sure forgot to take it apart.

suba · Post by **suba** » Mon Aug 24, 2009 11:33 pm

What about transmission mount? That could explain why the engine doesn't move when revved in neutral, but under load it could be flexing and hitting something on the underside of the car. I have nothing to back this up by the way, just spouting ideas.

evolutionmovement · Post by **evolutionmovement** » Tue Aug 25, 2009 1:40 am

By the descriptions, this sounds like a high frequency vibration. I would think a transmission mount would be a low frequency movement if it would vibrate at all. Not saying it can't be, but they usually show up as clunks and weight shifts. Important thing is to jack it up and check all the front end parts and wheels as that's a safety issue if they're bad enough to cause these symptoms. If you try rotating the wheels by hand while it's jacked up and in gear, you might be able to detect if there's too much free play in the CV joint. Then, too, the angle will be different than at rest, so it may not tell you anything at all. Could also be an internal transmission/clutch issue. Tough thing to diagnose by internet.

RJ93SS · Post by **RJ93SS** » Tue Aug 25, 2009 1:52 am

thanks guys, i'm going to get the wheels off tonight and have a look around. hopefully something pops out at me.

i was thinking today, i know my steering rack bushings are worn.
maybe the reason it only does it on acceleration and worst with harder throttle is torque steer as my rack is moving side to side.

like how front wheel drives pull to oneside when you gun it.

evolutionmovement · Post by **evolutionmovement** » Tue Aug 25, 2009 2:06 am

Maybe if they were gone, but it mostly makes a real sloppy steering. You'll have to check them with the tie rods anyway.

RJ93SS · Post by **RJ93SS** » Tue Aug 25, 2009 2:26 am

whats the best way to check the steering rack. what i was thinking i could do, put in the front wheels drive fuse, go for a drive to see if the problem persists. if it does, jack up the front end, start it and put it in drive, observe, have someone tap the throttle, observe feel for play.

both of my axels do have slight play in and out of the tranny. but they should right?

ericem · Post by **ericem** » Tue Aug 25, 2009 2:45 am

Ya they move in and out on the diff side. Did you check if there is play in the wheel at all? Maybe balljoint so many variables.

RJ93SS · Post by **RJ93SS** » Tue Aug 25, 2009 4:17 am

so, i put the front wheel drive fuse in and took it for a drive. felt exactley the same. then i jacked up the front end with the wheels on. i turned the car on and put it in drive. 1st thing i noticed is the front left axel is not turning round, as in a circle round. from watching the two axel's from above, i noticed that the front left one moved towards the front then back front then back like it was bent.

so, i'm obviously thinking the axel is bent unless something is wrong with my diff. i just dont see how you bend an axel, unless my single donut in the gravel or my hard cornering could do it.

play in the wheel side but both sides and it seems normal.

RJ93SS · Post by **RJ93SS** » Thu Aug 27, 2009 8:49 am

looks like diff bearings. i had a different mechanic than usual cause my guy is on holidays. i'll have more info next week.

log1call · Post by **log1call** » Fri Aug 28, 2009 2:06 am

If it's a bent axle it will be happening in time with the wheel turning. Put a wide piece of sticky tape on a tread and go for a drive. If the sound of the tape hitting the ground and the vibration are at the same speed it will probably be that axle.

I suspect though that it may be a miss-fire, especially if it's come after your adjusting the plug gaps and it is worse with heavier throttle. Try resetting the plugs to the reccommended setting and try it.

RJ93SS · Post by **RJ93SS** » Tue Sep 01, 2009 3:00 am

i'll find out tomorrow when i take it to my subie guy.
it's def. not a misfire cause you can see the axel move and shake. the diff must be f'd

ericem · Post by **ericem** » Tue Sep 01, 2009 5:21 am

log1call wrote:If it's a bent axle it will be happening in time with the wheel turning. Put a wide piece of sticky tape on a tread and go for a drive. If the sound of the tape hitting the ground and the vibration are at the same speed it will probably be that axle.

I suspect though that it may be a miss-fire, especially if it's come after your adjusting the plug gaps and it is worse with heavier throttle. Try resetting the plugs to the reccommended setting and try it.

maybe it's worse because he has more power!

RJ93SS · Post by **RJ93SS** » Wed Sep 02, 2009 3:50 am

it took my guy 5 minutes to figure out it was the inner plunge joint on the axel. better than a diff.

hopefully they will exchange, and thankfully i can do the work myself and my guy will check the alighnment for free.

legacycentral bbs

A forum for 89-94 BC-BF(BJ) Legacy Owners and Fans

weird shaking

weird shaking