BAD Vibration in car

[DSM_Zak]

Well as I bought my new DSM, there was a slight vibration. He told me the driveline was replaced and the motor was replaced with a 6 bolt since this was a 94 GSX. Well more and more driving I notice the vibration problem more and more. 1st and 2nd gear the car is mostly fine, maybe a LITTLE vibration after 3-3500RPM, but as I get higher in gears in 3rd 4th and 5th, the vibration gets worse and worse after 3-3500RPM. I dont htink its the balance shafts because if it was, it would be a constant vibration at a certain RPM through every gear, and the more you accel in the gear the harder it vibrates. In 4th gear the car gets really bad at full boost and feels like your sitting in a massage chair. It rattles everything in the car. I checked the U-Joints at work and they seemt o be fine, but I noticed that on every carrier bearing there was oil or grease slung up on the underside of the car. It almost feels like it happens mainly under boost, but I had an idea and thought it may have been the 14b out of balance so I went ahead and bought a used E316g, and the problem is still there.






Also -

The car has a wierd squeaking noise when you let the engine brake itself to slow down especially in lower gear, but when you give it some throttle it goes away, almost feels like two circular or rotary things are rubing metal to metal in a certain sop making a squeak squeak squeak noise. This ONLY does it when you have it in gear and let off the throttle and the car is braking with the engine. Also it does it in reverse as well, the only difference is when you GIVE it gas the squeaking gets worse and you can really hear it, it doesnt go away when gas is given. It's not the brakes, I checked them, and just resurfaced the two front rotors since when I bought the car they were warped. The car is in really good condition and has a good strong motor other than these two problems, the underside of the engine is really clean and dry no leaks etc etc its a JDM cyclone motor 6-bolt with 60k on it from Japan, yeah yeah people have thier opinions about JDM engine but whatever, 120k on the body and 60k on the motor all stock other than a boost controller when I bought it.

Any ideas?

 

[gsx rated98]

Have you taken it to a shop to have them look at the wheels and tires? A bent rim or a wheel out of balance may not show itself untill you get to higher speeds. A bent rim will act the same.

As far as the squeeking sound not sure. Id check the tranny and diff's fluids, see what kind of shape they are in. That could be a place to start with the squeeling noise. Thats just a guess though...

 

[travislaw]

You stated the car seems to vibrate while under boost. Did you check the motor mounts? I had a loose motor mount that squeeked like crazy. I cranked it down after installing Motor Mount inserts, no more vibration and no more squeeking. (I only installed the front and rear energy suspension motor mounts. $19 for them.)

 

[DSM_Zak]

Yeah I can check those. No I have not taken it to a mechanic, but I've thought about it. The vibration alsmost seems as the driveline but I'mno exactly sure. I'll check the motor mounts, but when the engine slows the car and you can kind of feel the engine "bounce" some when you sort of under-rev bog it you can hear the squeak come and go with the engine braking. Or like when I go down my driveway, downhill, I let off the clutch as I mostly neutral the whole thing but going downhil I let the engine brake and thats when you can really hear the squeak with the engine "bouncing" as you would say. I'll check those motor mounts and update as soon as I get home.

Also, when normal driving in 1st and 2nd there is not a single vibration. Its smooth running as it should until you reach, a decent amount of torque/boost

 

[EclipseTrbo420A]

CV joints

 

[DSM_Zak]

Wow - - what a long time its been since Ive looked at this. My car was down for a while and I just got it back up and running with a brand new E316g full ported by FP and 34mm flapper. EvoIII exhaust manifold and o2 housing match to an RRE 3" evoIII downpipe and test pipe, and to finish the exhaust I did an Apexi N1 cat-back. Sounds awsome, pulls great at 15psi of boost.

Well I replaced the carrier bearings thinking that was the issue with this mysterious vibration problem I have. After my first test drive, drove it, finally got into 3-5th gears same thing. Bad vibration. So I took it home pulled the wheels off since they are getting powdercoated, and looked at the front balance shaft. Its in time with everrthing as should be. Well I went to look at the rear, I put it at TDC, and stuck a screw driver in the plug on the back of the block, and it took the whole screwdriver (about 6"). I thought hmm lets see what it feels like if I turn the cams 1/4 turn. Did so, went back under the car it too the whole thing again. so I did another 1/4 turn went back under the car, and it took the whole
thing again. I am completly stumped to what this could be. I went through with the plugs, they seem fine, the wires seem fine (thinking maybe it needs a tune up).

I know its not:
Carrier bearings - replaced the whole driveline with new carrier bearings

Front Balance Shaft - it was in time with everything as it should be.

Rear balance shaft??? - Screw driver took more than 2.5" as VFAQ said it ATLEAST needed to take. It took the whole 6" screwdriver.

Its not the wheels or tires - I work at Les Schwab and balanced them when I first bought the car to start the process of elimination.

the look on my face while eating up a honda on the free way has me to something like

damn honda guy is in his car

Anyone have ANY ideas or suggestions? It pisses me off, I'm sick of having my rear view mirrior come loose and fall off.

 

[gsx rated98]

have you check to see if any of the wheels are bent? What about rotors? they could be badly warped as well.

Have you had the car aligned?

 

[Defiant]

3500rpm is where an out-of-phase rear balance shaft will take the fillings out of your teeth.

 

[w8lifter21]

3500rpm is where an out-of-phase rear balance shaft will take the fillings out of your teeth.

Next post answered this

 

[DSM_Zak]

Car was aligned when I got it as I work at les schwab. The Wheels are fine. Tires are fine. I cant seem to "feel" the rear balance shaft when I stick the screw driver in it. at TDC the thole screw driver goes in, 1/4 turn, still goes all the way in. at 180 from TDC, does the same thing.

 

[Defiant]

Sounds like it's been pulled. If you can't get a mirror up there to peek in, use a piece of wire to feel for it.
Check your transmission and motor mounts.
I don't go with the CV joint theory- I'd doubt one would shake that bad without making more noise than you could stand.

 

[DSM_Zak]

OK, so the new info that I have...

As I stuck my screwdriver in the hole I spun the cams to see if the screw driver would touch the balance shaft...it did...it jammed the screw driver down and pinned it so that you could move it in any direction at all so I DO KNOW there is one in there. So I'm assuming since I had everything at TDC at the cams and crank gears that the rear balance shaft is in phase correct? I didnt get a chance to see the oil pump gear, I was wondering if it was a tooth off if I would still be able to have the same vibration problem but yet still have the screw driver go all the way in the plug hole??

Second thought -

I pulled my drivers side motor mount and its shot. split on both sides to where I can pull the nipple where the bolt goes through and see inside the motor mount. I'm going to replace that this week, but I doubt that is the issue, the car vibrates at about 23-2400RPM and stops after the 4800ish RPM range and its smooth to redline...

 

[EclipseTrbo420A]

I just thought about something...My buddy was messing with his clutch and got everything back together but the car had your nasty vibration. He had a motor to tranny bolt loose and tightening ut up worked.

 

[DSM_Zak]

Here is another update.

Well, the vibration problem is still present and its really got me wondering what the hell it is. Me and my buddy were going out to a friends house, he was behind me in his RHD integra, and we were doing approx 120mph. I now know that the vibration is with speed. once its passed 42 or so MPH it starts to vibrate, and gets worse depending on the load you put on it. It does not vibrate in neutral either. Once I get passed the 72-75MPH mark its smooth sailing and runs and sounds beautiful. Well I guess that my buddy said there were 3 sparks that came out my exhaust while he was following me. After slowing down from 120-90MPH I got on it again and it vibrated badly as if it were in that MPH range that it vibrates with a heavy load.

Now it seems as if its starting to vibrate a little in the lower gears around the 20-30MPH range and dissapear until it hits the vibration MPH. It never did that before and it seems after I got on it hard last night up to 120 its kind of got this funnier feel now...



Second thought -
When I bought the car the guy told me it was a 60k mile JDM 6bolt swapped into it. I never actually got under the car to see if it really is a 6bolt but my clutch is sponge and needs to have the play adjusted out. I'm going to do that tonight but it seems as if the shifting is chunky. It has the GM synromesh in the tranny and it only has 124k on it. Reverse is a little twerky but I hear thats pretty usual with 1gs. I started thinking crankwalk but if its a 6 bolt thats pretty rare. Well, Hopfully someone will chime in with some answers!

My motor mount is still split like every normal DSM does, havnt gotten the chance to go get one but I know for a fact there is no way that thats the reason of the vibration.

 

[Defiant]

"we were doing approx 120mph"

We're done.