Hey guys my car started do something strange. While running smooth at low rmps under 2500 it's good. After 2500 i see rpm's needle jump up and Down and loose power then back to normal. In just this year I have replaced 2 ECM from autozone. Other than being bad ecm's could there be something taking out the ECM? I think the ECM is going out but I just change it about 4-5 months ago.

 

It appears you are saying the tach needle it jumping to indicate higher RPM, but the engine is not suddenly increasing speed to that RPM.

Could be the high resolution pulse signal from the optical cam position sensor in the Optispark distributor. Scan it for codes. If there's a problem, you will find DTC 36 or possibly DTC 16.

Why did you replace your PCM (93 was last year with ECM)? They seldom fail.

 

I had a similar problem and it ended up being the connector from the Optispark to the PCM, I.E. what Injuneer is saying.

-Dustin-

 

Sorry posted wrong info. I replaced the ICM not ECM. I did scan it but no codes came about. Yes correct tac needle jumps and when it does I feel a loose of power.

 

Could it be the transmission slipping above 2500rpm? when i first got my z the tranny would bounce off the rev limiter over 3000k in any gear... Might not be the issue just throwing it out there....

 

Not tranny related.

Today while driving to work 5 minute drive car shut off twice. First it turn over but didn't start. Then start then die again then start. Checked for codes and nothing.

 

How are you checking for codes?

 

I have the auto xray scanner. I've check for codes on it before I know it works.

 

So I check again with scanner hook up and I wiggle the harness attaching to ic
And car die. Unplugged it, plugged it back car starts. I check for codes and I get a 41 code electronic spark timing is open. I just touch the connector at ic
And car dies again.

 

As I wiggle the connector the car dies. Any idea how k can replace the connector it seems to not make a tight connection.

 

Shoebox has the part number for the ICM "pigtail" that will replace the connector. Look at the list in the right hand column:

http://shbox.com/1/Parts.htm

 

thanks for the help. im going to try to order it at dealership hope that solves the problem because after a while it would make sense that it would start to loosen up and eventually loose enough to throw a 41 code spark timing ope

Injuneer i know you may not have all the answer to everyone's problem. but how would i go about switching the wires to the one i buy?

 

Why are you buying it at a dealer? They will charge to 5X what it's worth.

Cut the old wires, strip and splice to the new wires. I prefer a soldered connection. Put a piece of heat shrink on each wire before your solder it, and slide the heat shrink up the wire away from the joint you are soldering. Wait for the joint to cool, slide the heat shrink over the joint and apply heat with a hair dryer or a heat gun. Make sure you spliced the wires in the exact sequence they were attached to the original harness connector.

 

well it looks like the connector i got from the dealer wont fit. the connector the car has is a square end connection. what i got from dealer is for a straight connecting. i didnt know where to buy so i went to dealer. autozone has it for 13. 67 but needs to be order.