hello everyone, i just lowered my car and got it alligned and all, but seems to vibrate when i press the gas, specially at higher speeds, any idea whats wrong, balance? cv joints?

It sounds like a case of pogo. Just change the strut mounts to a lower height and pogo will be reduced.

I haven't lowered my car, but i just take the car to align and balance, and still vibrating when hitting the gas or high speed, and it was a nail in my left front wheel.

Alex

I'd get your tires balanced first, just so you can rule that out.

this only happens when i accelerate, and expecially at low speeds.

did it do it before you lowered the car??

no it didnt, and they guy i delt with said it could be the one of the cv joint.

It doesnt sound like POGO if it only does it when you accel at low speeds. Not really sure what it could be because a vibration can be so many different things depending on how the vibration feels.

could it be a balance problem? cause its only doing it at certain speeds when i accelerate, if i get off the gas it doesnt do it anymore, yet this as only risen since car was lowered an inch.

Check all your front end hardware and make sure it
's all torqued properly. A bad CV joint will clunk when you make a 90 degree turn. Vibration could be from an outa balance tire, loose lugs, loose front end components etc. Oh and pogo is not a vibration. Pogo is the front ends tendancy to bounce excessively due to weak shocks. Lowered springs have a higher spring rate and unfortunately 90% of the struts available for our cars are not valved for a higher spring rate. Only ones I know of are the Koni adjustables and those things are outragous.

My 98 gtp has been vibrating ONLY under acelleration between speeds of 40mph and higher. I wish i knew what it was too!!!! it has nothing to do with tires or wheel balancing because the vibration would always be there , not just under acelleration. could it be the trans????

Hello,

I agree that worn parts in the front end will cause "Shudder".
Since you just had the car lowered, I would assume that the front end was in need of some attention before lowering, since all of a sudden you have the work done, and you experience the problem.
If everything checks out OK in the front end, there may be another issue with the powertrain.

TCC Shudder.
DEFINITION: An unacceptably long TCC apply occurs in third or fourth gear, Drive or Manual Third range, with the throttle held steady. This can cause a momentary rapid jerking sensation in the vehicle during the TCC apply.

From what I understand, this occurs mostly under light acceleration.
There are many causes of this, all of them are internal tranny issues, or the TC gone bad. It doesn't mean your tranny is bad, just that it needs attention, or the TC needs replacing.....IF this is what your problem is.

Later now,
Clint

how would i know if thats the problem, with the tranny, it was fine before lowering it, i have a feeling its cv joints, cause when i turn the wheeel max, it make a clunk noise. It also vibrates at high speeds when i press on it. But if you say something with the tranny, how can i test to see if thats the prob.

Hello,

I didn't say it was something with the tranny.
If I were you I would concentrate on the parts that are affected by the lowering of the car.

I brought up the TCC shudder for other members posting about similar symptoms, and for you, if the front end checks out OK.

From what I understand, TCC shudder happens at steady pressure, to light acceleration at around 50MPH. It is caused by the TCC slipping during a slow transition between 3rd and 4th gears.....I dunno for sure, but maybe running the car up to 60MPH or so in second gear to see if it vibrates would tell you if this is a problem.

There are a lot of moving parts between the Torque Converter, and the Wheels, It's hard to diagnose a vibration in that location while driving the car, much less over the internet.


Later now,
Clint

If I had a vibation problem, the first thing I would do is get the obvious thing done first. Balance the tires. When tires are out of balance they may not vibrate all the time. They can vibrate only at certain speeds. It really all depends on how out of balance they are.
From reading some of the issues above it sounds like balancing the tires are being overlooked because it doesn't happen all the time. I've had vibrations after I've rotated my tires, only at certain speeds, problem was tires out of balance.
Tires should be balance about every 10k miles because of the amount of rubber that is being worn off the tires will affect the balance of the tires.
In no way am I trying to dismiss any of the other problems that have been listed, just trying to help narrow down the options of problems.
One thing I learned in electronics is to always check the obvious first. If you're getting a vibration, get the tires balanced. If you still have the vibration, then you have ruled out the most common problem of vibration, instead of assuming that tire balance is not the problem and you're chasing things down.
The best way to get your tires balanced is on the car, but I dont think anyone does that anymore. When you balance the tires on the car, you're balancing everything that spins, tires, wheels, rotors, shaft, everything. Back in the day, the wheels went on the car in a certain postion from the factory. I don't think they do that anymore. On some older cars when you take the wheel off, you'll notice that one of the wheel studs have paint on the end. That lug is where you line up the valve stem, bacause the tires were balanced on the car from the factory.

Just my $0.02 worth, take it or leave it laying on the ground.