PLEASE HELP! Possible ECM Failure @ 109k miles?!

Here are the facts:

- It is a 2010 AC, 2.7L, 5-speed, 4x4 with 109k miles.
- A few days ago error code p0606 (ECM error) and p0138 (rear O2 sensor) appeared at the same time on my ultraguage.
- Truck seemed to be driving normally after the error codes and check engine light came on.
- I attempted to reset the ECM by disconnecting the battery for 10 min. This seemed to work for some people based on my research on here and other forums. However, this did not fix the problem for me.
- Upon start up, the truck has a low idle now.
- I'm towing my truck to a mechanic/family friend shop tonight.

Maybe there is a connection between the high volatge O2 sensor and the ECM error code. Should I ask my mechanic to replace the O2 sensor first and see if it was the cause the p0606 code? ...and still probably still have to reprogram the ECM

I wont know much more until he takes the ECM out Monday and performs diagnostic testing on it. As far as i can tell, the best case scenario, the ECM needs to be reprogrammed and worse case scenario replaced mad:$$$$)

Does anyone out there have any advice? Has this happened to anyone else, and if so what was the final diagnosis?

Please help! I dont want to pay for any unnecessary repairs. Thank you for any and all input!

 

a 606 codes usually means one of the rear o2 sensors is back feeding as its shorted out. i work at the dealer and see this all the time. replace the rear o2 for the p0138 code and clear and you should be fine

 

You have given me hope that this can all be resolved without cleaning out my bank account. Do you think the ECM will still need reprogramming or will is straighten itself out if given time?

 

Doesnt the ultragauge have a code clearing function?

 

im a tech at the dealer and i see the younger techs see that 606 and tell them its the ecm. they replace it and then it doesnt fix the problem
then i get it. and its always a failed rear 02 sensor back feeding the ecu and its freaks out and the 606 pops up. its always a o2 senor

 

Yeah. The codes cime back on pretty much right away

 

Yup failed rear sensor

 

Thank you for the info. Should I try to replace it myself? I do all my 9ther general maintenance (spark plugs, gear oil, etc) but I'm not an expert mechanic by any means.

 

It just screws out and unplug and screw in and plug in and clear code. Should be very simple as long as it's not super rusty

 

I just took a look under my truck, and both sensors seem look like they'll come out no problem. Seems like a simple enough swap. I'm thinking ill just replace both so I can know they were both done at the same mileage. I PB blasted them and hopefully everything will go well tomorrow. Should I pick up the parts from Toyota or will the one from NAPA/Autozone be just fine? Toyota is not especially convenient for me.

Also, is this going to fix the rough start/ low idle I've been experiencing since resetting the ECM?

Thanks again for the help, I really appreciate it. I no longer feel like pulling my hair out when I think about my truck.

 

keep us updated

 

Will do. I am hopeful that replacing the sensor will straighten everything out with the ECM.

 

the sensor will fix it. in 10+ years i have never put a ecu in a car or truck unless there was a actual issue with it or recall

 

I replaced both rear oxygen sensors this morning and reset the ecu. I drove around for 20 min or so after resetting the ecu and the error codes have not returned. The truck was idling low at first (450-500rpm) but after driving around its getting back to "normal" in the 550+ rpm range. I probably need a new battery, that thing is on its last legs.

 

After you clear the codes sometimes it has to relearn the idle. But it should be good to go

 

With your truck idling low after resetting the ecu I would suggest you take your throttle body off and clean it. They get gunked up and then the computer has to learn to use more fuel to get it to idle how it should. Super easy fix on these trucks.