Computer burnout problems

[Andrewb88]

I'm on my third computer and this one just burnt out. Just before it burns out I get a message on my crt screen saying there is an electrical problem with the engine. Then the car stammers at low speed bucking and non responsive to the gas pedal. I get aggressive it the engine smooths out with 1/2 pedal or more. I must say this started to happen after I cleaned the engine with gunk engine cleaner with a water rinse and compressed air to dry it off. The computers don't last 50 miles. I checked the on board diagnostics and do not show any active code, they are all history codes which have been addressed and corrected. It's been to the shop and they can't find anything causing this problem. They use the plug in under the dash system check. 

 

My car is an 88 with only 52k miles and is great condition except for this aging problem. My computer part number is 1228170.

 

Any suggestions ? 

 

Thanks

Andy

[TerryB]

They made lots of cars in 1988, would you care to narrow it down a bit by providing the the brand and model?

[Andrewb88]

Sorry, it's an 88 Buick Reatta.

 

Andy

[D-a-n-i-e-l]

Sounds like something is killing you ecm.

I would start with testing your injector signals, see if they are normal, check resistances of the injectors are close to each other, next I would look at your coil pack. Make sure it is firing and all the resistances on the coils are the same. 

Those would be my stating points.

[padgett]

That is a question for the Reatta forum. Lots of ECM (computer) information there.

Just as a guess I'd say either an overachieving alternator or a bad battery or bad wiring.

A sudden open on the battery with a high rate of charge going on can cause a spike in excess of 200 vdc.

[2seater]

I agree with the above suggestions that it sounds like a connection problem, more specifically a grounding problem possibly. Battery connection, which connects to three points from both sides of the battery. Ground is connected to the big terminal under the ICM, to the radiator header panel near the battery and the ground busbar inside the black plastic box on the fender behind the battery. There is also a large ground stud on the top rear passengers side corner of the engine, behind the power steering pump, sort of buried under the engine harness which connects to the injectors and other sensors. Most of what the ECM does to activate items is to switch their ground on and off, like the injectors, torque converter clutch and possibly others.

The battery plus side goes direct to the starter, the alternator output and the hot busbar inside the red plastic box on the fender just to the rear of the battery.

4 hours ago, padgett said:

That is a question for the Reatta forum. Lots of ECM (computer) information there.

Just as a guess I'd say either an overachieving alternator or a bad battery or bad wiring.

A sudden open on the battery with a high rate of charge going on can cause a spike in excess of 200 vdc.

Is that the correct ECM for an '88?? The part number doesn't sound right for an '89 or '90 but I haven't dealt with an '88 directly. 

[padgett]

1988 ECM 1228253 or 16198264, BCM 1227333. 

I show 88 89 Buick Reatta Riviera CRT Power Control Module ECC 1228170 (picture would help).

Edited April 25, 2021 by padgett (see edit history)

[2seater]

2 hours ago, padgett said:

1988 ECM 1228253 or 16198264, BCM 1227333. 

I show 88 89 Buick Reatta Riviera CRT Power Control Module ECC 1228170 (picture would help).

Ahh, made the assumption it was ECM but I had the 1228253 number stuck in my head, so it looked wrong. I didn't know how wrong😣 Many of the same suggestions apply but shouldn't affect engine performance unless I am missing something? The underhood wash would be more likely, especially where harnesses connect or sensors plug in. Look hard at the ones concerned with the ignition, but anything that can be disconnected, checked for moisture and plugged back in would be in order.

[Andrewb88]

Here is the story, I am a snow bird currently living in Florida and return to R.I. in the summer.

 

While in R.I. I had low speed stammering problems. Brought it to a garage and they told me my computer was burned out. It was replaced and ran good for 75 mike. Shipped the car to Florida , started doing the car here and the same thing started to happen. Brought the car to the local garage and they told me my computer was burned out and needs replacing. I had several part in Rhode Island from a donor 88 Reatta. The local garage told me the part number 1128170 and I said I had one in R.I., My grand son mailed it to me. The local garage swapped it out, ran good for 50 mile now again the same problem. As I do some investigating it looks like this is not the ecm computer. Here is a picture, maybe you guys can offer a suggestion. I started checking all the grounds, I ill start checking the resistance on the fuel injectors and the chills. 

 

Thanks

Andy

[2seater]

Does the CRT work? The module in the photo is definitely not the ECM and is called the information display module for the (CRT) for an '88, reman. If they are changing this module and the engine runs differently, something is very peculiar. Perhaps it is just coincidence and it simply runs better for a while until heat or vibration causes the issue to crop up? The ECM is located forward of the glove box, mounted vertically, with three large connectors on the bottom. Typically and engine that runs okay until warmed up that develops a misfire it is the coil pack and or ignition module below the pack. The ECM can also be subject to failure when hot. I suggest you or the mechanic visit the Reatta Owners Journal website and at the top of the page are links to diagnostics, repairs and a multitude of issues solved by actual owners over many years. 

 

Padgett mentioned the correct part numbers above.

Edited April 27, 2021 by 2seater (see edit history)

[Ronnie]

I'm not so sure the problem is a bad ECM. You said earlier, "Then the car stammers at low speed bucking and non responsive to the gas pedal."  My experience is that those symptoms usually aren't caused by a bad ECM. You said you had no current codes.  That leads me to suspect low fuel pressure or a faulty ignition system. Neither one of them will set a trouble code.

 

The first thing I would do is a complete fuel pressure check by using the instructions here on my website to rule out a faulty fuel pump.  Then I would swap out the Ignition control module and coils with some that are known to be good to rule out those parts as the cause of the problem. Next I would change the  crankshaft position sensor. Even something as simple as water in the gas or a bad MAF sensor can cause problems like you describe. 

 

If your mechanic in FL is relying on the diagnosis of the mechanic in RI you should find a new mechanic that will start troubleshooting from scratch and make his own diagnosis with basic troubleshooting that rules out fuel and spark delivery first.  Other causes should be ruled out before throwing more ECMs at it.

 

 

[padgett]

First picture, left on bottom row. Where in Florida ?

[Andrewb88]

Padgett,

 

  Great picture, I see it appears I am addressing the incorrect computer. After I clean all my connections under the hood I will take it to Advanced auto parts or somewhere to get a diagnosis and get the actual code. Until now I am replying on what the guys tell me. I'm pretty handy working on cars but nit the electrical stuff. Your help is greatly appreciated. 

 

I'm located in Port Saint Lucie Florida. Phone 401-241-6610

 

Thank you very much.

Andy

[padgett]

OK, about 125 miles from me over on the gold coast. Is the CRT working ? Reatta has a built in scan tool.

[Andrewb88]

Ronnie, I cleaned all. he grounds with sand paper and put a shine to them, reassembled with alight coating of dielectric grease. Next I'm doing to move the cool pack and clean the mounting pads and also the 

plug look pretty gross so you may be onto something here.

 

Thank you very much.

Andy

Padgett,

 

  CRT is working fine. I run a scan but no current codes just history codes. Orlando I see. Again, it looks like you have a wealth go knowledge based on the pictures. I do have some spare parts back in R.I. if you need something let me know.

 

 

Andy

Padgett,

 

  CRT is working fine, ran the code and all I got was history codes.

 

Andy

[Ronnie]

57 minutes ago, Andrewb88 said:

Next I'm doing to move the cool pack and clean the mounting pads and also the 

plug look pretty gross so you may be onto something here.

 

If the Ignition Control Module has green/gray goo on the side, like the one in the photo below, odds are the ICM is bad and should be replaced. The goo sometimes comes out and gets on the electrical plug as well.

 

 

[Andrewb88]

Ronnie,

 

  Mine looks exactly like that. I ordered a new coil pack and icu. Should be in next week. The plug is full of the green Gou too. I have some electrical cleaner, I hope it will clean it up.  I'll be in Vegas making a donation so I will not get back to working on the car until a week from Sunday.

Thanks for your help.

Andy