Sub-arctic yota

Looking for input before I start troubleshooting. I've done some internet searching, but haven't found any posts that match my symptoms.
Truck is an 89 pickup, 3VZ-E. Recently I started getting an intermittent CEL, once in a while it's been difficult to start or idles rough, but the overwhelming majority of the time it runs fine. If gas mileage has gotten poor, I haven't noticed yet.
I checked for codes, 2 flashes repeating is all I got. If I'm not mistaken this points to the AFM.
The CEL is now on steady, still running fine. I haven't checked codes again since the CEL became steady. I plan to do that, and check the AFM with an ohmmeter. Everything I've found on AFM codes, there is also a very obvious starting or running problem.
Just thought I would ask if anyone has seen this and found a resolution before I jump into it.
Thanks.

osv

my ecu is for early 22re, so i don't know how to read that, maybe post a video of it flashing, see if people agree with your diagnosis?? https://www.troublecodes.net/toyota/...up-or-4runner/

Jimkola

Could it be code 22?

Sub-arctic yota

Good ideas. Perhaps I am interpreting the flashes incorrectly. If it's 22, that would probably explain why the truck is still running okay.
I will check again, hopefully later today, and maybe post a video.
Thanks.

Sub-arctic yota

I checked codes again, and tried to upload a video, but I'm having trouble. I don't have time to figure it out right now.
I'm quite confident the code is 2. 2 flashes about 1.5 seconds apart, nothing for about a 4.5 seconds, 2 flashes 1.5 seconds apart, nothing for about 4.5 seconds, etc.
I may try to post video when I have more time.

Jimkola

I didn’t think 1989 had single digit codes.

2ToyGuy

Sounds more like a Code 22, not just 2. Might check what code 22 is, not code 2.

Good luck!
Pat☺

Sub-arctic yota

After more research, I believe it's a code 11.

Jimkola

TPS? Maybe the TPS spring return is getting sluggish. It's supposed to be pretty snappy on return, but I've seen them gum up and get pretty slow. I've read about ways to help free it up using penetrating oil.

Sub-arctic yota

TPS for code 11 doesn't seem right to me, but I'll check it out. I believe I saw that on other posts during my search.
Code 11 is "Momentary interruption in power supply to ECU". When the problem was intermittent, the CEL did seem to go on and off with the gas pedal.
I might start poking around with a meter today.
Thanks.

Sub-arctic yota

Update:
The Yota finally made it to the top of my "to do" list, and I think I found the problem.
I first checked the TPS. I figured since the truck is 35 years old, has 155k miles on it, and it was a pretty simple check, that I wanted to check it even though the code didn't point to it. The TPS is good. Now I know it's good, and it was an opportunity to use my old Simpson meter.
I have a battery disconnect on the negative terminal, and a friend recently told me that they can cause problems, so I looked at that next. I also still have the original terminal clamps on the truck, and they're in bad shape.
I removed the terminal clamps and battery disconnect, cleaned them up, and put them back on. I started the truck and let it idle for a little bit, drove it around the driveway a little bit, and parked it. No check engine light. The CEL was solid before, and when I cleared the code not too long ago, the CEL came back pretty quickly, so I think it's fixed. I'll find out for sure when I drive it more.
I'm glad Toyota used cables with ring terminals that bolt to the clamps, I will get some new, better quality clamps and replace the old ones, maybe military style clamps. I might remove the disconnect as well, although I like the benefit of having a disconnect.
I'm surprised there were no other indications of bad connections, I think maybe it wasn't cranking quite as fast as it should, but it wasn't really bad.