ECU issues?

Been having some trouble with the CEL intermittently going in and out. Today it came on while I was at a light idling and then shut off. Already tried to have it diagnosed at a local mechanic. They couldn’t read from the OBD and the light went off while they had it. When the light is on it seems like it’s in a limp mode and shutters a lot when initially giving it gas. The OBD port does work when the light is not on but when it’s on I can’t seem to get a read. Mechanic had the same trouble and said they tried three different scanners. Full tune up recently, cleaned the MAF everything seems to be okay. I same a couple other posts mentioning the ECU, so I went ahead and pulled that. Looks like two of the capacitors have some corrosion. Anyone ever replace any of these components in the ECU? Is it worth it or should I just try to pull a new one from the junkyard?

 

Wow....you guys need to form a club.......

https://www.tacomaworld.com/threads/not-out-of-woods-yet-intermittent-comm-ecm-loss.865349/

this movie keeps coming back....

https://www.tacomaworld.com/threads/1996-tacoma-ecm-stops-communicating.532116/#post-28029313


usually seems to be that 100uF one....

and sometimes and/or the 33uF

with these being so rare(96/97)......the junk yard option is around $700

 

Same boat

in my thread bigcarbon mentions 2 reputable RM companies

 

Is there something like an ignitor going bad, or rotor condenser going out, MAF taking a dump ....ect...causing this circuit to overheat,...

something that predates this....

seems to be unique to 96/97's

 

Well I’ve always heard to disconnect the battery before you do anything electrical or you can fry the ECM. Can’t help but suspect that maybe that wasn’t done somewhere in the former life of those vehicles with problems. Or else ground issues. Maybe didn’t fry it but started degrading it. I’m not an electronics guy but I’ve worked a full career in transmission voltages and substations. Electrical components wear out just like anything else. Surges, spikes, ground faults all accelerate that.

 

Capacitors fail, it's not an uncommon problem in the electronics world especially for 30 year old vehicles. Match up the caps on a reputable site like Mouser.com Digikey.com, don't buy them on Amazon or the like, and learn to solder or find someone that can.

I just replaced a "permanent" battery for the GPS unit in my HAM radio to save it from the scrap heap, for $8 and a few mins soldering. For reference the Manufacturer Yaesu told me I could send it in for repairs at $90/hr plus parts. This manufacturer is also known for scrubbing almost any trace of models that are not it's most recent.

 

As already said Caps are known to fail. I have seen it many times in main boards. It’s usually age related.

 

Appreciate all the help. I ended up sending it out to SIA electronics. I don’t trust myself with soldering. I’ve seen mixed reviews so I’ll update when they send it back.

 

Good call, definitely worth fixing rather than trying to replace

 

thanks for the tip AI253!


https://siaelec.com/product/toyota-tacoma-ecm-ecu-repair-return/

 

Darn right. Saving that link just in case.