really bad vibration

[gsxspeedlab]

my engine vibrates really bad from 4k to 7k rpm. it's really loud and seems to be more intense(by touch) by the throttle body and intake manifold. i took the EGR valve off and looked at it. it has a lot of build up in it. and my car is throwing an EGR code, but can that make that much vibration? thanks in advance.

 

[b00St3DgST]

my car used to virbrate really rough between 4-7K because of the rear motor mount not being bolted on. check ur mounts.

also, are ur balance shafts removed?

Shawn

 

[Defiant]

Also, confirm your timing and that your rear balance shaft isn't out-of-phase.

 

[laserspeeddemon]

Also, confirm your timing and that your rear balance shaft isn't out-of-phase.

When that screw ball mechanic did my T-belt thats exactly what the problem was.
Then when I did it, I also noticed he did not adjust the tensioner pulley either. So if you do this yourself make sure you do it right.

 

[zzzwilliams3200]

I dont think that it has anything to do with the code, but definitely check out your balance shaft belt because if it broke then it could take out your timing belt in short time.

 

[gsxspeedlab]

it did all start when i had my timing belt changed. the first time they did it, the timing was advanced. it ran great but idled really rough. so i took it back and they got the timing right but it made the vibration at 3k rpm. took it to a couple places including the mitsu dealer and they thought it was my BOV(crushed 1st gen) or wastegate. so i tightened all my hoses and checked my vacuum lines and it started making the noise later in the rpm range, at 4500 rpm or so. and i changed my flex pipe because the exhaust shop thought it was the problem becuase it was resonating through the exhaust and it changed rattle to about 5k rpm.

 

[zzzwilliams3200]

I'd bank on it being a rear balance shaft not being aligned properly, since this happened right after the timing belt was changed. There is a plug on the back of the block that they are supposed to take out to check the position of the counterweight of the balance shaft. My car used to vibrate and i decided to pull the engine and do some work, did all of the timing again and started it up the shake was gone.

 

[Defiant]

Yup, I just got back on the road today. You wouldn't believe the list of crap wrong. But top of the list was the timing 2 notches off, balance shaft out of phase, and as done by the Mitsubishi dealer

 

[gsxspeedlab]

well i'm taking my car back to the guy that changed out the belt tomorrow to ask him if he even checked the balance shaft. maybe i'll just have him cut the damn belt off. i didn't have that belt changed.

 

[gsxspeedlab]

i just got off the phone with the guy that changed my timing belt for me. he said he did check the position of the balance shaft. but also said there wasn't a seperate belt for it. guess i'll find out today, i'm taking it in for him to look at it. he's spent 4 days trying to figure out this problem before. i almost feel bad for doing it. oh well, guess i'll find out today.
is there a possibility it's my BOV or anything else?

 

[steve]

He correct that there isn't a seperate belt for the rear balance shaft since it's driven off the oil pump gears but there is for the front. Because the rear is driven off the pump gears the oil pump sprocket can line up with the timing marks and still be 180 degrees out of phase with the front balance shaft. Also you can't disconnect the front balance shaft without removing the rear one.

If in fact the shop managed to mistime the the belt installation and not just forget to adjust the ignition timing then I wouldn't be suprised if they messed up the balance shaft phasing the second time around.

Steve

 

[Defiant]

is there a possibility it's my BOV ?

Not any at all.

 

[dewdew]

My car just started doing this also, i had the engine rebuilt, including timing belt and b-shat eliminator, could something have come loose, shifted. is it bad to drive like this?

 

[laserspeeddemon]

is it bad to drive like this?

yes, if your car is every experiencing any problems, its never a good idea to keep driving it. You never know what small problem will result in catastrophic failure.

Here are some examples from this board, personal experiences, other boards, etc.

Symptom: A small knocking noise coming from the front passenger tire when turning
Cause: CV Boot was damaged. CV joint lost lubricant and debris got in
Cost to fix: about $30 to replace CV boot
Damage due to continued driving: loss of CV joint
Cost to fix after continued driving: replaced axle. abou $325.

Symptom: Strong Engine Vibration from 3000 rpms to 5500 rpms
Cause:bad timing alignment caused by unproper T-belt Tension.
cost to fix: about $120 to have timing belt reset.
Damage due to continued driving:Loss of Engine after timing slipped and dropped a valve
Cost to fix after continued driving:$3250

Symptom: metal on metal rubbing sound, noise worsened when braking.
Cause: damaged brake rotor
Cost to fix: about $100 to replace brakes
Damage due to continued driving: brake rotor shattered, causing rear tires to lock.
Cost to fix after continued driving:N/A (Car was totalled after being flipped)



you get the idea

 

[CMB12]

check the timing and motor mounts of course, but also check your rear diff! the rear diff can shutter and shake like a mofo if it is damaged. also not a very nice thing to fix if it is totally toasted from you driving it like that. its probly the timing stuff, but just food for thought

 

[gsxspeedlab]

AAAARRRGHH!! so i took the car back to the shop. the guy went through, replaced the timing belt with another new one, checked both of the b-shafts, and ran the car without the other belts on it to see any of those were the problem. he also checked the oil pump. well, it's no the timing, but it is coming from the motor. but we have NO idea what it could be. he mentioned the possibility of the flywheel being unbalanced, but that doesn't make any sense. another DSM buddy of mine didn't think so either.
anyway, still needing help. otherwise i'm going to set my car on fire.

EDIT: we're checking the motormounts today. i spaced it when i took it in there to mention that to him. here's hoping.

 

[unior]

just an idea if its not the motor:

rear carrier bearing can cause vibrations on acceleration

vfaq.com has info on a cheap fix

 

[gsxspeedlab]

it's not just under accelaration. the car can be out of gear and i can rev it slowly up to 7k. it starts vibrating at 4k or so, and gets progressively worse.

 

[Defiant]

Did he actually pull the plug and stick a screwdriver in the block to MAKE SURE the rear balance shaft isn't out of phase?

 

[gsxspeedlab]

yeah. and i didn't have to tell him anything about it either. and the motor mounts are all good. he checked those today. so now we have nothing. he's going to call all of his mechanic friends in the valley(that have their own shops as well) and see what they think. but any notions as to what it could be from you guys is GREATLY appreciated. otherwise i'm going to set my car on fire and buy another Saturn.

 

[b00St3DgST]

before u do that...let me get all the body pieces for the 97-99 conversion!

j/k man,u will get everything running right...it may take a while to figure out what it is exactly, but it will be all good and u will be able to boost again

 

[dewdew]

I just found my vibration problem, was the same thing. always vibrates at any rpm, clutch in or out, whenever. I found a damn bolt wedged between the tranny and crossmember causing all of my vibration!
I was pissed and excited all at the same time.

 

[MonsterEclipse]

idk if this was said already but if your oil pump is 180 degress off it will cause major vibration. I will check that out. peace

 

[BOBS90TURBO]

I had the same prob, and found out my Ballance shaft belt was busted since I bought the car, Well the T-belt jumped timing 3 teeth so I had it replaced and they also put on a B-shaft belt and it is like a new car, smooth as glass, before I could not go over 75mph because of the vibration, I am sure this is your problem, I'll bet your wrencher sucks and is trying to BS you.

 

[gthompson97]

i'm still betting your vibration problem is the balance shafts. most mechanics don't want to be "showed up" by their customers so they'll just say they know what they're doing and that they already checked that even if they didn't. there's nothing else it could really be except bad timing (the car would run shitty too though) or balance shafts. this might be something you have to fix on your own.