Hey,

Buddy of mine has an OBD 1 GSR setup and we have been having some issues. CEL doesn't illuminate at startup, VTEC doesnt kick, and the car is just not as fast as it should be. Previous owner did not use a full harness to swap to OBD1, so the wiring is a bit of a mess.

ECU is a P72-A01
First thing I tried to do was figure out why the CEL wasn't illuminating. Figured it was the bulb. Put a test light to the A13 wire at the ECU and there is no signal being sent at all for the CEL so I can't ground the A13 wire to read codes.

Secondly, The vtec pressure switch has power and ground to it, so I put a test light on the solenoid wire AT the ECU to see if it was giving the signal to the solenoid. He took it for a drive, watching the test light, and the car rev-limited at 5500 RPM. Took the test light off, car drove normally with a redline of ~7500.

Is this a bad ECU? No clue whats going on here, putting a test light on the VTEC solenoid wire shouldnt put the cart in limp mode. Even, so, I thought limp mode was 3500 RPM?

Thanks in advance.

 

Bump for insight.

 

bump for insight

 

Does the cel work at all? If not fix that and see if it's throwing any codes.

 

Use different ecu, check cel light bulb if it's taken out or dead, then change harness if all else fail.

 

It was throwing code 6 I replaced the sensor still throwing codes need to checkbit again