Renegade_Medic
New member
I have a 99 Cali spec 4runner and I'm having some persistent issues with my 7th injector controller, specifically the closed loop fuel enrichment. The controller appears to be doing its job properly, my OBD Scanner shows that the trucks AFR is running lean and steady when the enrichment starts, which tells me the URD controller is doing it's job. I think. The problem is that quite often my actual AFR will go to around 13:1, like it's supposed to, then plummet down to below 10:1, where my meter stops reading. The trucks ECU is seeing a steady "lean" O2 to make it go rich, but it is just getting carried away sometimes, but not others. I'm getting really frustrated with this.
My suspicion lies in 2 places, one is a bad ECU for one reason or another that is not happy with the way the URD controller is working. The other is that I had an occasional P0420 code due to a high flow cat. I have recently put on the URD O2 simulator in an attempt to get the P0420 code to go away. I know the computer uses the rear O2 sensor to calibrate the front and I'm trying to rule that out. It is still going full rich sometimes. Gadget at URD has had me try a bunch of things and can't seem to figure out why it is only sometimes doing it and not others.
Has anyone else had an issue similar to this?
My suspicion lies in 2 places, one is a bad ECU for one reason or another that is not happy with the way the URD controller is working. The other is that I had an occasional P0420 code due to a high flow cat. I have recently put on the URD O2 simulator in an attempt to get the P0420 code to go away. I know the computer uses the rear O2 sensor to calibrate the front and I'm trying to rule that out. It is still going full rich sometimes. Gadget at URD has had me try a bunch of things and can't seem to figure out why it is only sometimes doing it and not others.
Has anyone else had an issue similar to this?
