I have an 89 Beretta GT w/2.8. (Daughter'* school car) always starts when cold. After warm up it may or may not start. No codes set when checking ALDL (diagnostic mode). With engine running ALDL shorted (field serv mode) get fast serv eng soon blink, then slow blink, then constant on. Fuel pressure 44 ign on car off. 39 car running. No spark when cranking and no start. Tach in instrument cluster goes below 0 RPM when cranking. I don't have a SCAN tool or OBD 1 tester. Just a paper clip to short ALDL. Any ideas on where to look for this gremlin?
Thanks, Jim

I'd probably check the ignition module (front of engine, towards the bottom). I used to have an '89 Corsica, and, had the no spark when cranking/no start issue.

could be crank position sensor too, it will have the same symptoms. the ckp is on the back of the engine though, you can try heating the icm with a heat gun gently to see if it quits it not its likely the ckp

Thanks for the replies Bill & Justin. I replaced the ICM today and couldn't even get a cold start with the new one. Put the old one back on and it cranked right up. Taking the new one back to parts store tomorrow to have it tested. They tested the old one today (cold) and it tested good. If I had any hair, I'd be pullin' it out!

GM Modules always test "good" when cold, unless completely fried. Sometimes having them "tested" at a parts store is like giving a open book GED test at a methadone clinic.

Welcome to the forum Jim!
Sure would be nice to find some one with an OBD1 Scanner and obtain the stored codes!
Does Auto Zone have a OBD1 scanner available?
Does this help at all? http://www.obd-codes.com/faq/read-gm...codes-free.php

you dont want a aftermarket icm, you would be better with a junk yard gm one if you dont want to pay for a new one. sometimes rock auto has decent prices on delphi or delco ones. i agree with the test being useless though, unless you try heating it up with a heat gun or something

you can always test your icm with a test light if you can find the ground wire.your path of completion is through the ground side. so maybe do this while heating the icm.

test light should flash increasingly with engine rpm