Hi All-
I wanted to share my recent experience with sorting a trouble code 22 CEL issue I recently experienced with my 91 FJ80 (3FE.)
Basic synopsis of symptoms:
For the last month or so I began to see a very sporadic and short lived CEL illumination on my dash. It would come and go during long drives and would typically only stay illuminated for approximately 10 seconds. Having not spent much time with an ECU equipped vehicle (I come from the 24V/Diesel boards) I was unaware that I could check the trouble code after the light was no longer illuminated. I was under the impression that the light had to be actively lit to diagnose via the terminal shorting method on the diagnostic port. Thus I soldiered on and figured it would become progressively more common until I could capture it while stopped.
Fast forward two weeks ago, I was driving from Southern to Northern CA and arrived into the Bay area to the standard traffic scenario that turns what should be a 45 minute final approach into a 2 hour one. It was at this point, I began to notice a hesitation when I would step on the accelerator in traffic. The engine would stumble for 1-2 seconds (as if it was going to stall) and then "catch" and proceed as normal until I next was expected to accelerate from a low speed. I was obviously concerned that I would actually stall and further contribute to the traffic situation I so much loathed, so I progressively made my way to the slow lane such that in the event I did, I could more easily bail to the shoulder. My CEL came to life around this time but of course was gone by the time I was pull off the highway and ready to check.
I did some research that evening and quickly discovered that those CEL codes persist in non-volatile storage on the ECU such that they can be pulled until the ECU is explicitly reset (i.e. battery leads disconnected, or EFI fuse removed.) I went out to the truck and found error code 22, and 71.
It seemed a stretch that a faulty coolant sensor could be contributing to my issue of vehicle hesitation, besides by in dash gauge was perfectly functional? Of course it turns out that the sending unit for the gauge is an entirely different sensor than the switch that signals the ECU to alter the fuel-air mixture in accordance with engine temperature.
The following morning the truck refused to start. Repeated cranking made no difference which was unprecedented with this vehicle for me. I drove the 40 to work and ordered a new water temp sensor (
89422-20010) from Amazon: https://www.amazon.com/gp/product/B00FYIRS1W/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1
I replaced the sensor on Saturday and all of my starting and acceleration issues appear to be solved. I am attributing the error code 71 to an overly rich mix. I will report back in the event that see any CEL trouble codes.
Just thought I would share this for anyone experiencing similar issues.
Cheers,
Austin
I wanted to share my recent experience with sorting a trouble code 22 CEL issue I recently experienced with my 91 FJ80 (3FE.)
Basic synopsis of symptoms:
- Extreme idle (2500 on the high side, 300 on the low side)
- Trouble with cold starts
- Trouble with hot starts
- Hesitation on acceleration
- Trouble code 22 from CEL
For the last month or so I began to see a very sporadic and short lived CEL illumination on my dash. It would come and go during long drives and would typically only stay illuminated for approximately 10 seconds. Having not spent much time with an ECU equipped vehicle (I come from the 24V/Diesel boards) I was unaware that I could check the trouble code after the light was no longer illuminated. I was under the impression that the light had to be actively lit to diagnose via the terminal shorting method on the diagnostic port. Thus I soldiered on and figured it would become progressively more common until I could capture it while stopped.
Fast forward two weeks ago, I was driving from Southern to Northern CA and arrived into the Bay area to the standard traffic scenario that turns what should be a 45 minute final approach into a 2 hour one. It was at this point, I began to notice a hesitation when I would step on the accelerator in traffic. The engine would stumble for 1-2 seconds (as if it was going to stall) and then "catch" and proceed as normal until I next was expected to accelerate from a low speed. I was obviously concerned that I would actually stall and further contribute to the traffic situation I so much loathed, so I progressively made my way to the slow lane such that in the event I did, I could more easily bail to the shoulder. My CEL came to life around this time but of course was gone by the time I was pull off the highway and ready to check.
I did some research that evening and quickly discovered that those CEL codes persist in non-volatile storage on the ECU such that they can be pulled until the ECU is explicitly reset (i.e. battery leads disconnected, or EFI fuse removed.) I went out to the truck and found error code 22, and 71.
It seemed a stretch that a faulty coolant sensor could be contributing to my issue of vehicle hesitation, besides by in dash gauge was perfectly functional? Of course it turns out that the sending unit for the gauge is an entirely different sensor than the switch that signals the ECU to alter the fuel-air mixture in accordance with engine temperature.
The following morning the truck refused to start. Repeated cranking made no difference which was unprecedented with this vehicle for me. I drove the 40 to work and ordered a new water temp sensor (
89422-20010) from Amazon: https://www.amazon.com/gp/product/B00FYIRS1W/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1
I replaced the sensor on Saturday and all of my starting and acceleration issues appear to be solved. I am attributing the error code 71 to an overly rich mix. I will report back in the event that see any CEL trouble codes.
Just thought I would share this for anyone experiencing similar issues.
Cheers,
Austin
