1990 Reatta occasionally won't start

[Thunderpriest]

Greetings. My son has a 1990 Reatta that is giving him problems starting, and there appear to be too many reasons why this could be happening, making troubleshooting a real pain. 
Here are the symptoms: The car typically starts just fine. However, when he needs to go somewhere important - say, his job that is 45 mins away - it decides not to start. The car cranks hard, but doesn't turn over. My first thought was the ignition coil. (I removed a spark plug wire, put my key in it and held it next to metal, and saw no spark.) 
However, while doing very thorough research - uh, watching YouTube videos - it appears as though the security system might be coming into play. It seems as if the VATS key is not making proper contact due to the resistor being worn down - then it will not start. I have also seen similar symptoms listed when the ignition module needs to be replaced due to loose connections. He took the car to a repair shop, and it started for them a number of times without failing...so they didn't do any further troubleshooting. He drove it home. A few hours later, it would not start. It did start right up the following morning. The time between a failure and a successful start make me believe it could be VATS related.
I am trying to help him with his car as quickly and as cheaply as possible. (He just started his new job and has a VERY limited budget.)
If we replace the ignition Coil and it isn't the problem...that's just money down the drain, because parts stores won't that them back once installed. I don't think it can be tested.....so we are kinda stuck.
If anyone has any ideas, we would be extremely grateful for any advice.

 

[Ronnie]

17 hours ago, Thunderpriest said:

Here are the symptoms: The car typically starts just fine. However, when he needs to go somewhere important - say, his job that is 45 mins away - it decides not to start. The car cranks hard, but doesn't turn over. My first thought was the ignition coil. (I removed a spark plug wire, put my key in it and held it next to metal, and saw no spark.) 

 

Welcome to the forum! 

 

I assume you mean the starter will turn the engine but the engine will not fire up and run.  If that his the case you can rule out the VATS as the cause of  you problem. The VATS will prevent the starter from turning the engine.

 

Checking for spark is a good first step.  If you are certain there is no spark coming from the coils you have narrowed down your problem to a bad Ignition Control Module (ICM) or a bad crankshaft position sensor (CPS). Either on of those can cause the symptoms you describe and they WILL NOT set a code in diagnostics.  Another possibility is a bad ECM but you should eliminate the ICM and CPS as the cause first.

 

The next time the car will not start check for spark again to make certain there is no spark coming from the coils.  Also look for gray/green goo running down the side of the ICM as shown in the photo below.  That is a sure sign the ICM is failing.  The failure mode for the ICM usually is the engine dies when it runs for a while and gets hot and then starts up again after it cools back down. 

 

The failure mode for the CPS can be more erratic. Sometimes when it fails it will have the symptoms of a bad ICM and sometimes the engine just quits never starts again.  If you engine is failing to start randomly even when it's cold the CPS could be the problem but I would rule out the ICM as the problem first.

 

It would also be good to check the fuel pressure when the car won't start to rule that out as being a possibility. Most of the parts stores will loan you a fuel pressure tester if you don't have one.

 

 

[Thunderpriest]

Thank you so much for such a prompt reply.
Do you think I should have the ICM replaced instead of the Ignition Coil? I will inspect for the "gray/green goo".  
In trying to minimize the financial impact...I was hoping it was the coil...which is significantly cheaper than the control module.
The car obviously doesn't care which part is cheaper. LOL
I also am wondering if it is the CPS, as this problem can manifest when the car has been sitting idle for 30-45 mins. It does appear to be random. However, it always seems to start when left overnight.
I will definitely inspect the ICM and post pics if I find anything resembling what you had posted.
I hope to have this issue resolved soon so he can get back and forth to work on his own again, as I am currently driving him, which adds nearly 2 hours to my daily commute. 

Thanks again!!

[Ronnie]

The ICM, the part under the coils, is what usually goes bad when the engine won't start after getting hot.  Most people go to the salvage yard and get both IAC and coil pack as a unit. Price should be around $35 used. ICM new is expensive. If on a budget I would go the used route and save some money just in case that doesn't fix the problem.

 

I would try the ICM first. It is much easier to change than the CPS and more likely to fix the problem.

 

You might find this helpful. Ignition System Troubleshooting

Edited August 29, 2019 by Ronnie (see edit history)

[Thunderpriest]

Unfortunately, there are not a lot of Reattas floating around our local salvage yards.

This is my son's second Reatta, so he has scoured the salvage yards already. I will look on eBay.......perhaps I can find a used one there. (Though any 90's GM with the 3800 at the salvage yard should suffice, I would imagine?)

If not...and for the sake of expediency....we may have to purchase one new.
I have also seen that the CPS will be more difficult to swap. The "crank the engine with a braced breaker bar" procedure is a bit intimidating for someone who only works on cars when trouble/finances force the issue.
Luckily...I have a nephew who is good with working on cars who will be assisting.

[Ronnie]

The ICM/coils can come off any Buick with a 3800 of similar vintage. Most junk yards are full of them.  The large Buicks with a 3800 will work. It doesn't have to come off a Reatta. The guy at the parts counter at the salvage yard will be able to tell you what years to look for. Here is what the connector on the ICM should look like and what the bolts look like that hold it on.

 

 

 

[DAVES89]

In order for you to have the counter person sell you the "newer" style you would have to tell them you have a 1991 Reatta as that is the year GM switched over to the Delco Coil Pack ignition Control Module. Be sure to tell them you have the 3800 motor.

 Or if you want I can sell you a tested Magnavox Ignition Control Module. If interested you can e mail me at; lemke1044@aol.com

[Barney Eaton]

Also,   it does not need to be from a Reatta..........any GM 3800 V6 will have the same coil pack arrangement

I am not an expert,  so someone please correct me if this is wrong.

The original on your car will have all 3 coils molded into one assembly,  the later (improved) unit has 3 separate coils that can individually be removed

That is the one you want, with the connector shown above.   Thinking 1992 - 1998 vintage

[DAVES89]

5 hours ago, Barney Eaton said:

Also,   it does not need to be from a Reatta..........any GM 3800 V6 will have the same coil pack arrangement

I am not an expert,  so someone please correct me if this is wrong.

The original on your car will have all 3 coils molded into one assembly,  the later (improved) unit has 3 separate coils that can individually be removed

That is the one you want, with the connector shown above.   Thinking 1992 - 1998 vintage

The original has all three integrated and have square coil "boxes" were made by Magnavox. The newer ones by Delco have the "round" coils and is made by Delco. I believe you can go all the way to 2007.

[B Jake Moran]

Why not put new parts on.  (Original poster)

[padgett]

Cost, particularly if switching from a Magnavox to a Delco since you need everything: coils (3), ICM, mounting plate (flat used from 1991 to 1995), and hardware.

 

I put the part numbers in my article but not sure if current.

http://performanceresearch.us/padgett/cars/coils.htm

 

That said the symptoms sound more like a fuel pump not starting. There was a TSB on the issue. Try turning the key all the way off, was two seconds, then try to start again. I'd put a pressure gauge on the fuel rail.

 

Is the battery in excellent condition ?

 

ps I usually test by pouring about a 1/2 oz of gasoline into the intake (or spray about 3 seconds on starter fluid on the intake screen). Crank. If it pops off briefly, it is a fuel problem. If not, then ignition.

 

Where are you ?

 

Edited August 31, 2019 by padgett (see edit history)

[Thunderpriest]

In answer to some questions: 
1. Not buying new parts because my son just started  a new job and is strapped at the moment. Ideally, buying new parts is the best option....just not practical at the moment.
2. The battery is new.
3. I am located in South East Michigan.

Okay...so I am a bit hopeful and discouraged at once.
I did go to the local salvage yard, and they looked up an interchangeable part...an ICM from a 1992 Pontiac Bonneville. It was a BEAST to get off the car. Just the angle of working under the ICM on a car up on blocks was awkward...and the third bolt being up against another bolt made it impossible to use a socket. I used an open end wrench. So, All 3 mounting bolts were taken off blind.

 

Then...they wanted to charge me for the coil pack, as well. I had to unbolt the coils and remove...but the last one wouldn't budge. One screw was seized. I had to pay for it and then brought it home to try to remove. So, the bolt snapped off. The last coil is free....but that is one less screw hole available.
Now, the discouraging part. The ICM had the 3 separate coils....not the unified coil block. 
Will I still be able to use it? I am afraid it will not be compatible, based on what Padgett said above.
If I have to swap to the three coils, I would have been better off not taking them off the ICM to begin with. Kinda depressed by that thought, actually.
So, here is the ICM...after taking the coils off.

 

Do, I need the mounting plate...because I am fishing it out of my garbage can right now.
I am really frustrated, after thinking I was ready to swap the ICM in and potentially fix the problem.
The best part....the salvage yard is closed today if I do need more parts. 

Ugh.

[padgett]

I just leave the third nut off. Two has been enough for going on two decades.

[Thunderpriest]

Update:
Okay...so I was wrong. The salvage yard is open today. I went back to see if the coils I had removed yesterday were still on the counter. Nope.
All parts are collected at the end of the day and placed in a wheel barrow to be sorted and put out the following day.
They hadn't collected the parts yet.
Behold......

 

I will clean it up a bit....and then test it today. (I plan on just disconnecting the connector and spark plug wires from the current unit and attach them to the new unit without installing in the car to see if it will fire up.
Thanks for the continued suggestions and advice!!!

[Thunderpriest]

So, I put the new coil and ICM in and tried to start it. Had to do the full install, because the wiring module wouldn't reach otherwise.

No dice.

I don't know if the replacement is bad, or if I did something wrong. I put the old unit back in, and it won't start. It normally would have after sitting for hours.
I notice that when the key is turned to accessory, that there is a loud buzzing coming from somewhere in the dash. I will have to ask my son if that had been happening before....or if I screwed something up and made things worse.
Feeling really bad now, because I thought this would fix it for him.....and not only did I not fix it...I may have made it worse.

I wish I had better mechanics skills.

[padgett]

The pins in the connector are really short. First remove the sponge and then after tightening, tap the ends to full seat them.

 

BTW my recollection is that the ICM needs a ground through the plate.

[Thunderpriest]

The connectors on the wiring module?
Also...I am not sure what you mean by the ICM needing a ground through the plate. I have taken the ICM & Coils off as a unit and put them back on. (though I didn't put the nuts back on. It is sitting on the bracket so I can swap them easily.) I did not separate the coils from the ICM on the original unit.

I did have to disconnect a cable below the ICM to access the nuts under the bracket...and I believe it is a ground cable, because it comes from the negative battery terminal. I have reconnected it though.
So, I feel a bit lost at this point.

[Thunderpriest]

Okay...so I was doing some thinking about what Padgett said about it needing to be grounded through the plate. I went out and put the nuts on the mounting bolts and tightened them down. I also tightened the wiring module screw. (I am afraid of over tightening it and stripping it, though.)
The car started with the old coil and ICM.
Another thing. The car's dash has never worked right. It had an error on screen and my son was using GPS on his phone as a speedometer. However....when the car started...all of his gauges appeared.
Is it a problem with the negative ground? 
I am not satisfied that  the problem is fixed after a single start. I am letting the car get hot and will try starting again later.

 

[Thunderpriest]

So, I let the car get hot, and it won't start again. I will wait for it to cool down...swap the coil pack and try again after making sure that everything is tight.

[padgett]

There should be a large chassis ground with from the engine to the body on the passenger side. Bad ground will screw up the display. If missing it will try to ground through the shifter cable but that does not work well.

[Thunderpriest]

I will have to look for the ground cable to verify. The instrument panel display worked for a few minutes, but went out when I changed the coil pack. I figure it is a bad ground wire or bad connection. I believe either instance will cause the start problems we have been seeing, correct?
Additionally...I checked the fuses and found that the "Body" fuse was melted. Could this be the result of the bad ground, and could this contribute to the problem? The cables on the negative terminal of the battery rotate easily. Should they be tighter? (I believe the prior owner used a bolt+nut combination to have a better post to connect jumpers to and I don't know if this is contributing.)
My nephew is going to bring over his OBD 2 scanner with an ODB 1 adapter to scan the car, but I am not too optimistic. I have tried 2 ignition coils/ICMs and always get the same result. Starts right up the 1st time.....won't start when it heats up.
CPS? BDM? Bad Ground?
Ugh

Oh...and we were able to verify fuel at the fuel rail....eliminating the pump as the problem.
As usual...thank for the advice!

 

[padgett]

Did you realize that Reattas have a built in scan tool ? Turn key on and hold OFF and WARMER on the HVAC until it flashes.

 

Cables you can rotate in your hand are not making a good connection.

[Thunderpriest]

I know next to nothing about Reattas. LOL
I have done some work on my own cars with a Chilton's manual.....but I am just a weekend mechanic at best. (Thank God for YouTube!)
Will that procedure work if the instrument panel is dead?

 

 

Edited September 4, 2019 by Thunderpriest (see edit history)