Vibration.. HELP!!

[chaseevans72089]

I HAVE A 95 GT 5 SPD. I HAVE A VIBRATION THAT I THOUGHT WAS A MISFIRE. BUT CONCLUDED THAT ITS NOT. IT VIBRATES MOST IN 2ND GEAR FROM 1800 TO 2500 RPM AND THEN GOES AWAY. ALSO VIBRATES A LITTLE IN 4TH BUT NOT NEAR AS BAD (BARELY NOTICEABLE). I DID NOTICE THAT THE SHIFTER SHAKES ALSO WHILE THIS IS HAPPENING BUT NOT AS BAD IN 2ND AS IT IS IN FOURTH. DOESNT MAKE MUCH SENSE. A BUDDY OF MINE SAID HE THINKS ITS THE OUTPUT SHAFT BUSHING. I JUST BOUGHT THE CAR A COUPLE WEEKS AGO. IT SAT FOR A COUPLE OF YEARS. THEY COULD NOT GET IT RUNNING AND AFTER THEY THREW A FUEL PUMP AND FILTER AT IT THEY GAVE UP. I BOUGHT IT AND FIXED THE GAS LEAK AROUND THE FILLER NECK GASKET AND FILLED IT UP WITH GAS AND IT RAN FINE. HAD A MISFIRE AND I REPLACED NUMBER 5 INJECTOR AND CLEARED IT UP. RAN CODES AND CYLINDER BALANCE TEST AND ONLY CODE IS 172 CODE. I FIXED ONE VACUME LEAK AND DONT SEE ANYMORE SO IM STILL CHASING THIS LEAN CODE BUT MY BIGGEST CONCERN IS THE VIBRATION. I ALSO REPLACED THE HARMONIC BALANCER. ANYBODY ELSE KNOW WHAT IT COULD BE?

 

[Win]

Look at your harmonic balancer see if you see any rubber squeezing out inbetween

 

[CC'S95GT]

Look at your harmonic balancer see if you see any rubber squeezing out inbetween

agreed. the HB rubber dries out and then slips. then your timing and balance is off (hence the vibration). I've already replaced mine.
Stock replacement is fine but if you can afford it why not upgrade to a better quality.

code 172, clean your MAF and IAC .

BTW welcome to the madness

 

[Win]

agreed. the HB rubber dries out and then slips. then your timing and balance is off (hence the vibration). I've already replaced mine.
Stock replacement is fine but if you can afford it why not upgrade to a better quality.

code 172, clean your MAF and IAC .

BTW welcome to the madness

oh gosh it was so blurred together I didn't even see the code 172


sorry about that guy

 

[CC'S95GT]

I got your back.

 

[chaseevans72089]

I have already replaced the harmonic balancer. I have also already cleaned the MAF. I have not tried cleaning the IAC. If the IAC was acting up would it not throw lean codes on both banks? the 172 code is just lean on bank 1. I will try the it anyways. I am just curious. thanks

 

[chaseevans72089]

how would the timing be off just from the balancer being shifted? I figure the timing would stay the same unless I tried changing the timing with the balancer being shifted giving incorrect timing mark readings??

 

[Win]

I have already replaced the harmonic balancer. I have also already cleaned the MAF. I have not tried cleaning the IAC. If the IAC was acting up would it not throw lean codes on both banks? the 172 code is just lean on bank 1. I will try the it anyways. I am just curious. thanks

When did you replace it... Did it do this after you replaced it? You could have gotten. Bad one. It won't always throw codes on both or even 1 bank.

The timing can be off from the balancer... Check with the spout out and see what it says....

 

[chaseevans72089]

ok I will give you another update on the history. I bought the car and fixed the misfire plugs, wires, cap, rotor button and (number 5 injector) had vibration from day 1.

still had vibration and I checked the balancer and it was bad so I replaced it and then put my timing at 12 degrees with spout out.

vibration is still the same.

I cleaned MAF and had no change. it seems I can feel vibration in the shifter

 

[CC'S95GT]

The HB has a inner steel hub and an outer steel ring. The 2 are held together with a rubber like seal. When the rubber dries out it allows the inner and outer to slip. Then the 50oz balance is thrown off. hence the vibration.
Do you get the vibration sitting still or only when moving?

You o2 sensor might also be causing the code. You could swap the O2's to the other side to see if the code transfers.
When I got those lean codes it was from a dirty MAF from having a K&N filter installed. I replaced the K&N with a paper filter, cleaned the MAF and haven't gotten that code again.

 

[chaseevans72089]

I COMPLETELY understand how the balancer is held together, and EXACTLY what it does and how it works. I have stated twice already it has been replaced.

I have also stated that it only vibrates in second gear until 2500 rpm and then goes away. Does not matter whether under load or not.

 

[Win]

We're not beig rude but your saying up till 2500 rpms which is such a common issue with a HB... Unless the PO blew the clutch and damaged the flywheel and its all sorts of screwed.

 

[chaseevans72089]

I know you guys are trying to help and not being rude. I just didn't want to beat this thread to death about the balancer. I have searched this forum up and down before this post so I made sure to check everything that I have read (balancer being one of them) to avoid this exact situation lol. no worries though. Im just frustrated. vibration piss me off.

 

[chaseevans72089]

the previous owner did put a clutch in it and sometimes I smell it burning after I pull out of my steep driveway. I don't really ride the clutch and it still stinks like its burning sometimes when it shouldn't. I wonder if that might be the problem im having.

 

[chris91]

When was the last time the tires were balanced? Have you checked the Ujoints on the driveshaft? Or the driveshaft itself? Sometimes the weights will fall off the driveshaft throwing it off balance.

 

[CC'S95GT]

I know your frustrated. Were throwing out suggestions fo the most common reasons. It's difficult to diagnose these things without actually being in the car for ourselves.
Maybe the balancer is loose. Maybe the drive shaft os loose. Motor/trans mount? Misaligned clutch?

your clutch definately sounds out of adjustment too. Does it still have the stock quadrant?

We've delt with a lot of rookies and since your new we don't know your skill level. glad to have you here non the less

 

[5litrarag]

Is the vibration there ONLY when the car is moving or does it do it when sitting still?
If you can push the clutch in, rev up and still get the vibration, your problem is in front of the trans. And if so, well, you just bought yourself a rebuild project.

You said you replaced the balancer...did you buy a NEW piece or did you just toss on one that you had laying around?

 

[uncltrvlnmatt]

Drain the trans and check the magnetic plug and oil for debris. I think you may be looking in he wrong direction. It vibrates mostly in second gear and a little in forth, but has a vibration in the shifter in second. Check the trans.

 

[GT Rob]

What win said had it happened to me

 

[chaseevans72089]

Yea it only does it in second under throttle.. If I push in clutch it goes away.
The balancer was replaced with new.
i have checked the u joints but didn't look at the driveshaft itself. I will check the weights on the driveshaft this weekend.
Thanks