Vibration

[Cobra18]

I am working on my 93 Cobra and am getting frustrated trying to figure out my vibration issue. I have a SSP computer ,AEM Cold Air intake, stock MAF sensor in the chrome AEM housing, 24lb injectors, stock TB, 1.6 Scorpion Street Roller Rockers, F303 cam, 302 bored .040 over, King Cobra clutch,Street wire MSD coil. I have a bad vibration that shakes the the mid section of the car at 2500 rpms.It will shake very slightly when in neutral but really bad when driving. I just had my aluminum driveshaft balanced, new motor mounts, new tranny mount. It almost seems like to me that it is a misfire but all of my plugs look like they are burning just fine. I have 150-155 psi in all cylinders, spark plug wires all ohm'ed out to be good. At times the vibration is so bad that I can feel it in the pedals. Also Any ideas would defiunately be appreciated.

[1993cobra]

Make sure you installed the correct balancer, flywheel, clutch, also make sure you a can designed for your firing order not the older non ho order.

[WillyB93]

Also make sure you don't have any plug wires arching across each other, I like to do that at night. You should be able to see a blue arch if they are bad, or you could just ohm's test the wires to make sure there is no breakage in the wire.

[Cobra18]

The plug wires and plugs seem to be fine. I pulled them out and checked them. None of them are wet and are burning really clean! If I have an SSP computer in the car with a 6000 performance chip, is it ok to run codes with a Scan tool?

[Mike S.]

Sounds clutch related. Pulling it apart to inspect the components may be the next step.

-MJS

[casper]

make sure the pressure plate has guide pins, had one vibrate bad one time because the whole pressure plate was off center. you can look in fork hole.

[Cobra18]

I have an issue with what seems to be a vibration at 2500 rpms. I pulled out the ECM today and noticed that it says SSP on it. I called Ford and they informed me that the 93 Cobras have a specific ECM and cant use a regular mustang ECM due to the MAF being calibrated as 24lb injectors. Does this sound familiar to anyone? Also the idle surges when its cold and also at idle it almost seems like there is a miss and engine loading up...I am running a AEM cold air intake with a K&N cone filter on the end. I just need to know my next step as to whether replace ECM or replace MAF with one calibrated for 24lb injectors.Can the ECM be programmed to calibrate the MAF for 24lb injectors?

[1993cobra]

it came with a X3Z code on the ecm , im guessing ssp means that it came out of a special service car, and probably just a A9L ? do you have 24lb injectors and the correct MAF? if so, start looking for a X3Z, or yes you can a custom chip made for the A9L.

[casper]

tell us how this started, buy car with problem ? just start doing it out of the blue? you done any kind of work to it then it started.?

[Cobra18]

When I bought the car it had a vibration only when I got on it hard and now it vibrates even with normal driving. I will be pulling the transmission tomorrow and checking the flywheel and see if I can see anything else in there that could be loose or bad

[1993cobra]

check all your engine and trans mounts, and make sure nothing is touching or rubbing the body, exhaust included.

[casper]

check all your engine and trans mounts, and make sure nothing is touching or rubbing the body, exhaust included.

x2 check tranny mount first

[Cobra18]

SOLVED!!!!! I have figured out the vibration. After running the numbers on the flywheel, it happened to be a 28in/oz imbalance flywheel when it is supposed to be 50in/oz imbalance. That would definately be my vibration issue.

[escogt]

Glad you got it all figured out. That would have driven me nuts also.