Bad Vibration

[datdude407]

Ok here is te story of my Z. I purchased a white with tan interior 1990 300zx Na 5 spd T-top coupe last may with the intentions of having a sweet daily driver. I brought the car with 2 bad injectors. The car had been driven for years with only 4 cylinders. After the long and aggonizing replacement of all injectors, ecu, ptu, cam angle sensor, spark plugs and oil, I was still getting ecu code 35. It just so happens that the ecu that i purchased was for a Cali car (I live in Orlado, Fl). I placed an 68k ohm resistor in the EGR sylenoids. I have no ecu codes, and my car is still not running a 100% Im experiencing a feeling of my car kind of hessitating or chocking while accelerating. I am also experiencing bad vibration while accelerating. I talked to a couple of Z guys in my area and i was told either engine mount, transmission mount or driveshaft due to the prolonged driving the car with only 4 working injectors.Can somebody please point me in the right direction.

[robomatic12]

We won't be able to diagnose a vibration problem other than suggestions, this is something you will have to find for yourself under the car.

Have somone get in the car, with the car in gear and the handbrake on, try to move the car forwards (while the handbrake holds you in gear) if the engine rocks excessively, the mounts are probably toast.

You can get under the car with it safely up on jack stands and try to move the transmission mount, look for any torn rubber (the same goes for engine mounts).

Wiggle the center bearing of the driveshaft to see if it has any play in it, it should not have any play.

When do you get the vibration? Just acceleration, not deacceleration? Any speed/rpm?

[es.biggs]

Could be a lot of things...I had a wicked bad vibration at certain RPMs while accelerating when I first bought the car...turned out to be the ignition timing was way off - my CAS needed to be adjusted. If that sounds like your problem, you can check it with a timing light.

[datdude407]

It turned out to be bad differential, sub frame bushings & I had to clock the Z1 driveshaft 90 degrees. It took me to do a clutch & flywheel upgrade to figure it out.