90 Regal GS will not start

[francerichard]

My GS started doing something weird the other day and now it is getting worse. Sometimes it will start right up, and sometimes it will only turn over. When it will not start, the service engine soon and low coolant lights are flashing. As long as these lights are flashing it will not start period. If you leave the key on, it may take 10 minutes or more, the lights stop flashing and it will start right up and run fine. I have checked and cleaned all the grounds, but still the same thing. Any ideas? Thanks in advance, Richard

[francerichard]

Anyone?

[Mickey#1]

I'm not familar with the older Regals, what motor do you have?

[francerichard]

It is a 3.1 with 163000 miles on it. Up until this problem started, it has been a very dependable car.

[Mickey#1]

Are any relays &/or solenoids in the engine compartment clicking while the SES & coolant lights are flashing?

[francerichard]

The only thing I can hear or feel clicking under the hood is the idle speed controller. When it stops clicking, the lights have stopped flashing. I have disconnected isc when the lights are flashing, but no change. as long as those two lights are flashing, it will not start.

[Mickey#1]

You might have a bad computer. Did you check for any codes?

[francerichard]

I put the scanner on it and no codes. When I had the scanner plugged in, and turned the key on, The lights were flashing, and the screen on the scanner said that communication with the vehicle had been lost. Without disconnecting the scanner, I waited a while and turned the key on, the lights stayed on steady, the scanner was communicating, but no codes.

[Mickey#1]

Check your connections at the battery. Most of the GM cars have two positive cables that come together under a rubber boot. Pull the bolts from the cables & remove the rubber boots. Clean the bolts & both sides of the cable ends & spacer. Apply dielectric and reassemble.

If cleaning the cables doesn't help then I'd pick up another computer (ECM) from a junkyard. Swap the PROM chip from your ECM into the replacement.

[richtazz]

That Regal has a split positive cable. One branch goes to the starter, the other to the underhood fuse/relay center. Check the cable and the underside of the relay center for corrosion. If that all checks out, you either have a bad ECM (very common issue on these cars due to being mounted under the hood) or a bad ignition switch.

[francerichard]

Thanks, I will check all this out. By the way, does any on have a factory service manual in pdf format?

[francerichard]

I checked all battery cables and they are clean and tight. I unbolted the relay center and it also is clean and everything is tight. I will see if I can find a used ecu and try it.

[francerichard]

Well, it looks as if I have a bad battery. After the car sits all night, it will start, then if I shut it off right away and try to restart it, the lights will start flashing and it will not start. When I put the battery charger on it, It shows that the battery is almost totally discharged. I took it to Auto Zone and had it tested, the charging system checked out fine but the battery didn't. So for now, untill I can afford to buy a battery, I will just keep the charger on it. Thanks for all the help. I still need a service manual in pdf format if anyone has it. Thanks, again.

[francerichard]

Well, I put a new battery in it and thought it was fixed but I was wrong. I drove to my brothers and coming home after driving about 80 miles, and the engine started cutting out and the service engine and low coolant lights started flashing and it died. I was running 65 mph at the time. I coasted to the side of the road and waited about 10 minutes, turned the key on, and the lights weren't flashing so I started it up and drove the remaining 25 miles home without any problems. I'm about to pull my hair out on this one. I don't know where to go to from here.

[francerichard]

Ideas? Anyone?