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crjspo23
08-22-2012, 03:59 PM
I posted some history under another thread for Cam Position Sensor, but here is the problem. After no issues for 2 years, the car started missing suddenly about 10 seconds after startup. The SES light came on and was traced to fault code 31 - Cam Position sensor. The sensor was checked and determined not to be the problem, but in the course of suspicion of the common injector problems in 90-92's a couple of bad injectors were found. New Delphi SS injectors were ordered and installed, but upon startup the car still ran as if on 5-6 cylinders and then stalled and wouldn't restart. Fuel pressure was checked and is fine. Spark plugs were pulled and checked and are fine and do not appear to have been flooded with fuel and we do have spark.

Anybody got any other ideas of where to look to find this elusive problem?
mike100
08-22-2012, 06:13 PM
do a compression and/or leak-down check on the cylinders.
gbrtng
08-22-2012, 06:26 PM
something under the plenum is out of ordre - hosed up during the injector replacement.
GOLDCYLON
08-22-2012, 08:00 PM
something under the plenum is out of ordre - hosed up during the injector replacement.



Yep Bent pin etc, check the wiring you might have pinched something
rhipsher
08-22-2012, 09:44 PM
Check to see if the MAP hose is unplugged.
crjspo23
08-23-2012, 04:48 PM
Actually traced back to a bad ECM. Anybody know sources to find one or get one rebuilt?
gbrtng
08-23-2012, 06:15 PM
Actually traced back to a bad ECM. Anybody know sources to find one or get one rebuilt?
A good possibility - what led you to that conclusion?
tccrab
08-24-2012, 12:48 PM
New ECMs have become very scarce and very pricey indeed.
I remember a thread a few months ago which referenced a company that refurbished our particular ECMs.
I will have to go digging around to find it.
Don't get false hope if you should find an ECM listed on some car parts web site.
It'll be for the L98 or the LT1 not the LT5.

Check with Marc Haibec, he'll either have one or know where to get one.

'Crabs
ScottZ95ZR1
08-24-2012, 02:18 PM
I have a known good, used ECM out of a low-mile '91. I'm really not looking to sell it but if you absolutely can't find one send me a PM.
GOLDCYLON
08-24-2012, 02:22 PM
I believe Kurt White has a rescource on this for the rebuilds he is on here as LIMEY

Its a rebuild service with a quick turn around

http://www.whiteracingproducts.com/


I have used Kurt repeatedly for scarce parts.
crjspo23
09-03-2012, 09:20 AM
I ended up finding a rebuild service thru Rock Auto for about $200. The other source I found was Kurt White Racing - he had rebuiult ECM's in stock but they are $699. NAPA also will rebuild and will send it from any store for about $250 - probably the same rebuild service as Rock Auto (A-1 Cardone).
scottfab
09-03-2012, 11:52 AM
I ended up finding a rebuild service thru Rock Auto for about $200. The other source I found was Kurt White Racing - he had rebuiult ECM's in stock but they are $699. NAPA also will rebuild and will send it from any store for about $250 - probably the same rebuild service as Rock Auto (A-1 Cardone).

I would strongly suggest you do the following on the suspected "bad" ECM.
1. inspect all pins and straighten and bent ones. Also (and this is important) look for broken off pins.
2. pull the chip and re-seat it.
3. flex the wire harness a bit and reattach the ECM.

I have two ECMs and use to swap it out to get through the
state emissions test. Sometimes the connectors would become
not fully seated or???? When I pulled and reconnected all was fine.

I am curious on how you came to the conclusion it was a bad ECM?
I mean did you swap in a known good one?