BamaYota1

Hi guys, I'm the new guy. I have a 93 4x4 Pickup w/ 22re and 5 speed. When I bought the truck, it had the wonderful code 52 issue. I ran a new wire from the ECU to the knock sensor, and the code cleared. But now I have a question. The PO had the knock sensor tapped to a yellow wire with a blue stripe. So my question is, what is the yellow with blue stripe supposed to be wired to? I am going to cut open the loom in a bit and trace where things go, but any help would be appreciated.

Thanks in advance.

scope103

Well, I don't have much to go on.

Does "PO had the knock sensor tapped to a yellow wire with a blue stripe " mean "Prior Owner had the knock sensor WIRE TAPED to a yellow wire with a blue stripe"? The only wire I can find with that color is IDL from the TPS. You seem to be saying the Y-L (Yellow with blue) wire goes to "Sensor Ground." Do you mean E21? http://www.ncttora.com/fsm/1990-1995...e/troubles.pdf E21 is the ground for the TPS (it should be brown-black) and should be in the same bundle with Y-L from the TPS.

The only connection to the Knock Sensor should be the core wire of the shielded knock sensor wire. The shield connects back at the ECM; it's unconnected at the Sensor.

I'm just going from schematics; I have a slim hope that Toyota is consistent with wire colors, but I have no guarantee that any of that is true.

BamaYota1

I meant that he had the lead to the sensor tapped to a yellow wire with blue stripe. I ran a new wire for the knock sensor, so I have fixed that problem. My concern is the wire that the previous owner had running to the sensor should be connected to something.

I was wrong about where the same color wire terminated into the ecu. It is actually the next wire over. From the pinout I found, it looks to be the volume air flow meter, but that is pure conjecture.

I do not have any codes at the moment.

BamaYota1

Thanks for the link. I will start on this again in the morning and check voltages at the ecu.