Bad CPS?

[RobertK]

Just finished installing a timing belt on my 89 325is. Replaced the spark plug wires, spark plugs, ignition cap/rotor, v-belts, flushed the cooling system, etc.

I think it might be worth mentioning that I pressure washed the engine bay once I took the timing belt out.

The first time I drive it the car drives great except it hesitates like its hitting a rev limiter at 4200rpm?.. I call a friend and be mentions double checking the crank balancer to make sure it is true. I pull everything out, resecure the balancer, and now when I drive it hesistate at 5k.

Could this be the CPS?

[jlevie]

A bad CPS is a possibility, as is a bad harmonic balancer, but there are other possibilities. The first thing I'd want to know is what is the fuel pressure when the engine misbehaves.

[lolcantturn]

Just finished installing a timing belt on my 89 325is. Replaced the spark plug wires, spark plugs, ignition cap/rotor, v-belts, flushed the cooling system, etc.

I think it might be worth mentioning that I pressure washed the engine bay once I took the timing belt out.

The first time I drive it the car drives great except it hesitates like its hitting a rev limiter at 4200rpm?.. I call a friend and be mentions double checking the crank balancer to make sure it is true. I pull everything out, resecure the balancer, and now when I drive it hesistate at 5k.

Could this be the CPS?

Sounds exactly like my problem. Except after it hesistated, it shut off momentarily.
Guess what it was?
the CPS.
Just measure the resistance it puts out. Or just take it out and inspect the wires, should take 5 minutes to have it out of the car.

[RobertK]

Sounds exactly like my problem. Except after it hesistated, it shut off momentarily.
Guess what it was?
the CPS.
Just measure the resistance it puts out. Or just take it out and inspect the wires, should take 5 minutes to have it out of the car.

It did that on my first test run.

After letting it sit over night now its just fine. I have a feeling I'm going to need to replace my CPS very soon.

[IRON-E]

Yeap, had this issue before, even if you get enough power to get your car running., a cracked or exposed wires CPS will cause these problems including bucking under acceleration.

Change it and your problem will be solved.