1996 Tacoma ECM stops communicating

I have a 1996 Tacoma that will start and run great then after a few minutes of driving the engine light comes on. I have tried to connect it to the computer and it read link failure. The port has worked in the past so I know its not the problem I have read codes before and replaced parts. The fuse is good. The computer stops communicating with the truck. If the AC is on when the ECM fails the compressor also stops running and the engine has poor performance, (air flow/ gas mixture) so this lets me know that the ECM looses total communication. I have went use other scanners and have has the same outcome. When reading some of the forums some issues are caused by a loss of ground. So before i go purchase a ECM I wanted to see if anyone has had this same problem before.

Thanks In Advance

 

Any luck with your Tacoma? I think I have the same problem that you're having on my 1996 Toyota Tacoma

 

No Sir, i took the computer out and inspected it and not resistors/chips are damaged. It all looks like a new card. I went and drive it again yesterday and it starts fine then after about 5 - 10 minutes it stops communicating with the truck. I can go get in it now and it will do the same thing so im not sure if its the computer or when its running a scan on all the instruments one of them might be grounded. No blown fuses so im lost. any help appreciated. would be nice if i can get a code but it will say link error when engine light comes on.

 

Yes sir I know what you mean mine is doing the exact same thing. Took the computer out of mine also and like you said looks like a brand new board. Haven't come to any conclusion of what it might be yet but if I find out anything I will definitely keep you in mind and let you know. And if you find out anything on yours if you would please let me know thank you.

 

I might just go ahead and buy a use ECM off the internet and see what happens. But, if i do resolve it i will let you know.

 

Thanks a lot and I will keep you posted if I come up with anything.

 

Just thought I'd let you know I purchased a used ECM off eBay placed it in the truck and so far no problems everything is working good.

 

Thanks think I’m going that route also

 

Anytime hope everything works out fine for you also. been driving truck for for 3 days now and no issues.

 

Did you have to do some sort of VIN-based reprograming/flashing the ECM? Thanks

 

Hey guys any updates? I have the same problem but we've tried everything to test. Truck goes into limp mode after about an hour of driving, engine light comes on lose ac, let it sit for about 20 min. And can drive another 30 before it repeats. Tried to recreate and my mechanic had been all over it tying to find the problem fuel pump, o2 sensor, maf sensors, etc, maybe ecm? Any way to test it? Or any successful solutions?

 

If your engine light still comes on you likely have a functioning ECU. First sign of a failed one is lack of a light, then communication to a scanner.

With your truck I would personally suspect an igniter module, I would probably try a used one if I could find one at a wrecker.

 

No problem with starting is will run fine all week with 30 min - 1 hour running around town trips without any problems. Then on the weekends I have a 2 hour drive there and back. always goes into limp mode after an 1hr have to stop and let it sit for 20 min.(not overheating) goes into limp mode with no and no reading off engine light
Replaced:
Fuel pump
Fuel filter
Tune up with new plugs, wires, anddistributor cap.
Throttle body cleaned
Oxygen sensors checked good
New MAF
Anyone have ideas?

 

I know this is an old thread but came across it and it helped me greatly. Will review what happened to my truck and hopefully my experience will help the next unfortunate soul to have this happen.
Had the CEL coming on intermittently, every time it did the truck would loose power/bog drastically. Sometimes the CEL would stay on for 20 minutes at a time, sometimes it would flash on and off constantly every couple seconds.....each time same thing would happen, power loss/bogging.....trying to accelerate was virtually impossible, the truck even stalled while at idle a bunch of times but would start right back up.
Tried scanning the truck with multiple different OBDII scanners but every time the CEL was on the scanners would say that there was no communication with the OBDII. While the CEL was off every scanner was actually able to connect to the OBDII but not when the CEL was on. Found info about doing the OBDI connector (in engine bay) jump to find out which code is actually being thrown:

https://www.2carpros.com/articles/t...finitions-and-code-gathering-method-1990-1995

My truck displayed Code 11:

Code 11 Momentary interruption in power supply to ECU (electronic control unit or computer)

Worst case scenario, the ECU had/is taking a dump. Pulled the ECU and noticed that there was some "sticky brown liquid" on each of the three connectors where they plug into the ECU. Took the top cover of the ECU off and saw a little bit of the same "sticky brown liquid" on one edge of the circuit board. Sprayed everything completely with CRC Electronic Cleaner and let it air dry. Connected everything back and my truck started right back up, idling perfectly and the best part, NO CHECK ENGINE LIGHT!! Drove it around for about an hour and no issues thus far, runs perfect.
I'll do a follow up within the next couple days and hopefully have continued good news.

 

Having same issue no communication comes up on scanner probably send mine off to get checked

 

Mine started back doing it again after 2 days. Ordered a reman ECU ($500, lifetime warranty) just waiting for it to arrive

 

Welcome to TW!

 

I have had the same issue with my 1996 Tacoma 2.4L AT.
The only codes that came up were misfire cylinders 2, 3 and 4 and multiple misfire.
The truck would run perfect to the store and then when I start it again it would run the same as you described.

I opened the EMC and found that 2 capacitors were blown.
One pin was in tack while the other pin was burn away off the board.
One capacitor was 10v 100uF and the other was 35v 33uF.
I desoldered the old ones and resoldered new Panasonic ones from Amazon.

One thing I also noticed is that when my truck was is good running condition if the MAF was disconnected the truck will turn off.
When it was running bad as described the MAF would be disconnected, and the truck would still run.
When the truck was running bad I also had my AC system stop working, it would stall at stop lights and run with alot of misfire and no power.
The OBD scanner would also not work and state communication error when it is running bad.
When it was running good I could scan the truck no issue.

Here are some pictures of my ECM.
Kind of an old thread but I hope that this helps someone with the same issue.
I have driven the truck so far three times locally with no issues, I will continue driving it longer to see if the issue has been resolved.
I can also scan the truck and have not had any codes appear yet.

 

If anyone is ever in need of an ecu let me know. Red Heeler Harnesses has been providing ecu's to people world wide!