No spark in 1995 Riviera

Hello fellas,

I just picked up a sweet 1995 Riviera 3800 Supercharged for $300 but it has a problem - no start/spark. It has 120,000 miles and is in impeccable shape. Here is what I know about the car: The vents where the wipers are apparently became clogged with leaves and then the drain clogged. Needless to say, water during rainstorms late this summer wound up backing up into the dash and onto the floor. The inside was not flooded by any means but the previous owner wound up using towels to soak up the water on the front floor.
Within days of the water backing up into the interior, the power seat died. Then, the car would randomly shut down when driving. Then maybe some time later, it could be restarted. It was brought to a local mechanic, and after a day's worth or messing with it, both the car's owner and mechanic gave up on the car. Now, a few months later of sitting at the mechanic's, I bought it and now it just cranks and there is no spark.
I have many questions. One is is this 95 Riv, OBD 1 or OBD 2 - I would lean towards OBD 1 - but apparently from what I read, it can go either way?
Now regarding no spark, I am scratching my head. I pulled the ECM from behind the glove box and it is a refurbished one. I noticed some corrosion on the bottom of the heater blower motor from where water must have been leaking in. The ECM is right next to this blower, so I feel like moisture could have damaged the ECM. I took the ECM apart (torx screws) and didn't see any corrosion or moisture in the ECM...I have been told that mechanics have seen ECMS with actual water or condensation in them...but my unit looked ok - no water, moisture or corrosion.
Before I begin replacing stuff, what should be the first thing I do? I can get a used ECM from a local yard for $75. I know crank position sensors go bad,but it would be all too coincidental considering the water leak and then this problem with dying out occured, which leads me to believe the ECM may be bad.
Are there any ways to check an ECM? Is there any way to see if 12 volts is getting to the coil packs? The car just cranks and cranks with no spark.
Sorry for rambling, but I need help and don't have a bundle to bring this to a dealer with a scanner and have them replace stuff and rape me - I'd rather buy a scanner if I have to.
Any help or things I can check would be appreciated!!

Do you know anyone who has a Tech II (GM factory) scanner? That wil lhelp.

WARNING - THE FOLLOWING IS ALL SPECULATION (maybe even hallucination).

My guess is it's not the ECM but the BCM and/or MALL that are shot. Also at 120K miles maybe the crank sensor faile but that is why youwant a Tech II so you can test the sensors and such instead of guessing.

Also you might think about removing the interior and fixing the (surface) rust that will be under the carpet padding. The BCM is under the drivers seat, if it got wet it might be running the VATS starter disable, which would give you a nostart condition.

ALso if you do figure out what computer(s) need replaced you might be able to get Ed Morad to quote you a package price on 'em. Do a search on this list to find Morad's web site.

If the VATS starter disable is running, would it still allow the car to crank and just not start? I am not familiar with VATS...if you could elaborate.

If the power seat stopped working, maybe it is the BCM after all, which controls the power seat wouldn't you think?

I called a local junkyard and they have a 1995 Riviera there. $75 for a ECM and I would think maybe they would make me a package deal on both if I purchased them.

Is there any way to get around the VATS starter disable - maybe bypassing it? If that VATS was acting up due to a bad BCM, would that shut the car off when driving down the road, because that was one of the first symptoms after the water soaked the rug. Now, it won't fire at all...

I don't have anyone I know with GM Tools....any scanners out there that I could purchase for a decent price that can work?

It wouldn't crank if it was the VATS. It would just blink the security light at you. At least on the 98s..

I'm sure you already checked this but is the battery charged? You will hear the starter clicking if the battery is dead could that be it?

The battery was dead but I jumped it with a running car and the Riviera turns over/cranks fine - motor is spinning normal, it just doesn't fire. I checked for spark at the coil when cranking and there is none.

I plan on trickle charging the battery for at least 24 hours...the battery isn't too old at all so it should be fine.

Is there any way to "jump" the coil packs to just test run/hot wire (so to speak lol) to get this car running?

Any ideas on where I should begin to get this car running again?

Ok...

I decide to look under the drivers seat at the BCM module and see alot of stuff is corroded and rusted. I decide to remove both seats and sure enough the BCM is bolted to a sheetmetal bracket that is entirely rusted. I then remove the sill plates and lift up the carpet. Well there must have been about an inch of water under the carpet on the rear floor driver side. The entire foam backing was drenched. I noticed some corrosion on a few plugs that went to the seat motor etc.
I attempted to remove the console, but I cant get the gearshift knob off. Anyone know how to remove this? I need to get that off so the console comes off and then I can remove the entire carpet so that everything dries out completely.
My next question is simple. Is there anything under the carpeting that once got wet could cause a no spark condition. Assuming the BCM is shot, does that control anything as far as spark? The car turns over fine/cranks, but doesn't fire because there is no spark present. Could the water have shorted out the ECM due to wet wiring under the carpet?
Any advice or next steps that I should take? Thanks for any help!

Fastfrankie wrote:

Ok...

I decide to look under the drivers seat at the BCM module and see alot of stuff is corroded and rusted. I decide to remove both seats and sure enough the BCM is bolted to a sheetmetal bracket that is entirely rusted. I then remove the sill plates and lift up the carpet. Well there must have been about an inch of water under the carpet on the rear floor driver side. The entire foam backing was drenched. I noticed some corrosion on a few plugs that went to the seat motor etc.
I attempted to remove the console, but I cant get the gearshift knob off. Anyone know how to remove this? I need to get that off so the console comes off and then I can remove the entire carpet so that everything dries out completely.
My next question is simple. Is there anything under the carpeting that once got wet could cause a no spark condition. Assuming the BCM is shot, does that control anything as far as spark? The car turns over fine/cranks, but doesn't fire because there is no spark present. Could the water have shorted out the ECM due to wet wiring under the carpet?
Any advice or next steps that I should take? Thanks for any help!

Sorry I stole your pictures Jack, but figured I'd answer since no one else had.
Fastfrankie, you can go here for complete console removal, thanks to "Jack the R"
https://rivperformance.editboard.com/Interior-f20/Write-Up-BD-Trims-Wood-Dash-Kit-Install-t1341.htm

One thing- go to CarQuest or AutoZone and get yourself a couple cans of LectraMotive (I think that is what it is called) and a can of Qhick Dry electronic cleaner. They are CRC chemicals that will help you clean up the wiring mess without killing the platic insulation. Be sure to follow the label directions.

As for that shift knob, I know there is a retainer clip under the base of the knob that holds the knob on. I have never had to take mine off so I can't tell you anymore - the service manual just says to remove the retainer, then pull off the shift knob by lifting up.

ONe way to figure this out is to go to a pull-it-yourself junkyard and try to take one off a car having a simlar knob Many GM cars (chevy cavalier) around the same years have the same shift knob, just maybe not leather covered. You will know it when you see it.

As for the BCM, you may want to check EBay for a service manual so you can have not only wiring diagrams but also charts that show how the modules operate and that give you some ideas for troubleshooting. It will cost you less to do that - at least in terms of time lost - than it will cost you in time to come back and forth to this bulletin board for advice that could be looked up.

albertj