My brother has a 1990 Sedan DeVille with the Port Fuel Injected 4.5l V8. One day it just died, and now it won't start. The fuel pump is coming on - there's NO spark. We hooked up an inline spark tester - NOTHING! He put a new pickup coil on the distributor - NOTHING! All the relays have power going into them and all the fuses are good. The coil and module both test good. Power is going into the coil. Apparently, there's something we're missing.o No: What else should be checked? It figures...the car was running fine and he had the car sold - NOW THIS?? You gotta love it!
If there's a "service engine soon" light on, that means the ECM is giving a code telling what is wrong. Now, if the engine is dead and there is no "service engine soon" light then, there might be something wrong with the ECM itself. Usually, if something is wrong with the engine the ECM will give a code out to tell you what could possibly be wrong. Rob
Forgot to mention that - NO check engine light comes on (it works, just isn't pulling any codes). There is NO crank sensor on these - works off the distributor. We do suspect the computer might have gone.o No: Hoping to find one to try. Seems like the only thing left that makes sense.
You might try turning the key on, and checking the pink wire on the ignition module at the distributor for 12v+. That should go directly to the ignition switch. I have wiring diagrams I can fax you or print out and scan and email them or post them if you need them. Mike
Mike - I'll double check that. Power is definitely going IN to the coil - I'll make sure the module is getting power too. Rob - They still used distributors. *Assuming the module is getting 12+volts, would it appear that the ECM might be the culprit? Thanks for the help!!:TU:
ECM could be the culprit. ... you might try the tap and twist test on it and see if it starts. Early 90's GM's had some really crappy quality pc boards.
Not positive on this one, but I guess that the timing chain ain't turning. If it has one of those cheesy nylon timing gears that Buick used, ACK!!! Make sure your distributor is turning. -Bob Cunningham bobc@gnttype.org
Does his Caddy have the theft-deterent system with the ignition key with the diode in it? If it does, and the diode comes out of the key, the car won't start. My 90 Reatta has this system and since his Caddy is a 90 I thought it might have it, too. Not sure exactly how it works.....but it's easy to check. But new keys aren't cheap.
We tried rapping on the computer - No Change! We even tried a small shot of starting fluid - Nothing! Bob - I thought the same thing, so we pulled the cap and cranked her over - looks to be turning fine! The key does have the PASS pellet in it. I don't recall anything out of the ordinary with it. I'll tell him to inspect the key. *The engine was running fine. The problem seemed to just happen all of a sudden!o No: I'm guessing electrical or the computer. You can still hear the pump kick on when the key is turned on. That was initially our first thought - pump and filter. We wish!! All suggestions are appreciated - keep 'em coming! We'll get this thing narrowed down and running sooner or later.:grin:
Just gave my brother a quick call. He said the last couple of days that it was running - it kind of acted like it was starving for fuel.o No: Yet, the pump still kicks on?! It's definitely not getting any kind of spark whatsoever! To the best of our knowledge, the dist. controls when the fuel gets fired thru the injectors (plus the ECM, of course). Could it work the other way around? If the fuel isn't up to snuff, could it shut down the spark all together?? Thanks again!:TU:
