My ZR-1 is wigging out bad!!!

[ffvetteman]

I started my 92 ZR-1 for the first time in over a month and all hell broke loose.

My check engine light stayed on along with my 'service ASR' light. I could not turn on the power key either. And I drove it around the block and noticed the digital temp sensor was not working, but the guage was. Then about ever 20 seconds, the security light would flash and at the sme time it would flash 'sys' where the digital readout for the temp should be. It would flash 3 times then go back to normal and start all over again about 20 second later.

It also was holding an idle of about 1800-2000RPM. And when I turned the key to start the cooling fan would start right away.

The car is all stock except for the Samco duct and the DRM chip. I put the stock chip it and it made no difference.

The good news is the service ride control light is off now that I tightened the cap nut.

Where do I start??

I did disconnect the battery for a few hours, which made no diference.

Any one got any ideas?

[Peaven]

Did you try to pull the codes yet? I'd grab your service manual and start there first....good luck.

Get ready to buy a ECM. I had the same symptoms before mine died.

[ffvetteman]

Originally Posted by Jeffvette

Get ready to buy a ECM. I had the same symptoms before mine died.

Thats the first thing I thought of yeasterday. The problem I have is that Im not good with diaganosing electrial problems. I can fix mechanical problems all day long, and fix wiring all day long but not good with finding electrial problems. At this point Im not sure where to start.

Ill take a look into pulling codes next. I just dont linke the ides of grounding out the ALDL on this car. Ive done it on other cars, but not cars that are as nice as this.

[ffvetteman]

Is the ECM something I can just buy from somewhere, or have mine fixed?

Just curious.

[ffvetteman]

Alright, step 1, check the codes.

Grounded A and B, wurned the key on and....'SES' light did nothing but stay on.

No code 12, no flash at all.

Just for fun checked the SIR light, - code 12.

Checked the ride control light - code 12.

Checked the serial data (ASR) - ASR light stayed on - no flash.

Checked the 'SES" light many more times - nothing stayed on - no flash.

Doing more reading - Im thinking ECM may be toast.

[ffvetteman]

Did more reading. When the SES light does not flash it sends you to another chart. It told me to disconnect the ECM connectors and ground out CKT 419 test the SES light. It said that wire should be brn/wht. Mine in that spot was yellow, so I did not ground it. But the SES light is working, So it lead me to the ECM is bad or bad connection at the ECM. All the connects at the ECM are clean so I think the ECM is bad.

Any thoughts?

[ffvetteman]

Where do I start looking for a ECM?

[Dandy97]

I just bought a rebuilt one from partsamerica.com for $145.00 plus shipping, no core charge. P/N is 16163993. This was the only place I could find one other than White Racing, but Kurt wants $380.00 plus a $200.00 core charge. Let me know if you want to try it in your car to see if it solves the problem. I'm not using it in my car, I bought it as a spare.

[guinnessdood]

Originally Posted by ffvetteman

Where do I start looking for a ECM?

Is there someone close by that can loan you an ECM to try?...Marc Haibeck may have one to loan and he is near Chicago. My ECM died a couple years back with different symptoms, but that doesn't matter...the ECM controls so many things that any of them could go South and cause different symptoms. Did you by chance try tapping on the ECM while tha car is idling? Mine would really flake out when I did that...thus verifying that it was indeed the ECM. I'm an old F-4 Radar guy and my fave tool was a hammer...:-) Good for finding intermittent problems! You won't have to tap on the ECM very hard to get it to act up if it is like mine was.

Uly