I've got an 89 FJ62 and for the past few weeks I've had issues with code 21 :/
At first this happened whilst accelerating (either from a complete stop OR an an engine restart). Eventually that behavior went away - and transitioned to happening every other time I restart the engine immediately after a refuel. I desmogged the engine last week; the cats are gone but the O2 sensors remain; the O2 sensors are aftermarket but they're not malfunctioning. I tested the car all week, driving nearly 200 miles, thru 90+ degree days in metro atlanta traffic; the CEL never went off no matter what I threw (or had thrown) at her. The first and second times I refueled, nothing happened. But the third time the CEL went off. (Like I said, this is the pattern as of late, every other refuel or so). The CEL went away immediately at the next restart.
Naturally I looked through every thread that covers code 21 but none fit this behavior (there was one thread with the code coming on during an acceleration that I want to study a bit since I did experience that initially). Some other info - I replaced the fuel pump and fuel pulsation dampener months ago; the O2 sensors themselves are about 1 year old; I also replaced the ECU after I spotted water damage to it (LONG story there); she's got grounding issues at the rear that appear at random.
So I guess my questions are - has anyone ever experienced this? - aside from the O2 sensor tests in the FSM, what else might I want to do or look out for - and, how likely is this just a random electrical gremlin? I'm inclined to believe a combo of faulty grounding, 30+ year old wiring, and random flukes mimic the conditions that trigger this code.
At first this happened whilst accelerating (either from a complete stop OR an an engine restart). Eventually that behavior went away - and transitioned to happening every other time I restart the engine immediately after a refuel. I desmogged the engine last week; the cats are gone but the O2 sensors remain; the O2 sensors are aftermarket but they're not malfunctioning. I tested the car all week, driving nearly 200 miles, thru 90+ degree days in metro atlanta traffic; the CEL never went off no matter what I threw (or had thrown) at her. The first and second times I refueled, nothing happened. But the third time the CEL went off. (Like I said, this is the pattern as of late, every other refuel or so). The CEL went away immediately at the next restart.
Naturally I looked through every thread that covers code 21 but none fit this behavior (there was one thread with the code coming on during an acceleration that I want to study a bit since I did experience that initially). Some other info - I replaced the fuel pump and fuel pulsation dampener months ago; the O2 sensors themselves are about 1 year old; I also replaced the ECU after I spotted water damage to it (LONG story there); she's got grounding issues at the rear that appear at random.
So I guess my questions are - has anyone ever experienced this? - aside from the O2 sensor tests in the FSM, what else might I want to do or look out for - and, how likely is this just a random electrical gremlin? I'm inclined to believe a combo of faulty grounding, 30+ year old wiring, and random flukes mimic the conditions that trigger this code.
