caldixiechick
Probationary Member
- 19
- 8
- Nov 8, 2021
-
Shingle Springs,
California
My 90 Laser is very hard to start when cold (sitting overnight) and is throwing CEL code 14. When it finally starts it runs and idles just fine and will start normally until it’s cold again. The TPS was bad, so I found a good one, replaced it and adjusted it based on the info in the factory and Haynes book. After leaving the battery disconnected overnight to charge it, CEL 14 is still coming up. Further testing and there’s no voltage on the harness side of the TPS plug. According to the books it’s supposed to have 5 volts. I thought that the idle position sensor might be bad but then why would it idle fine?
What I’m trying to figure out is there something between the harness plug and the ECU, or where the wires go from the harness plug. I’m not finding a lot of info on this circuit in the wiring diagrams and I’m new at reading them. I have the 90 specific factory manuals and Haynes.
I’m hoping someone has run into the same issue and can share how they fixed it. I think my next step is figuring out if the circuit in the ECU is damaged? Or I’m totally barking up the wrong tree.
Fortunately the wiring in my car hasn’t been hacked up by previous owners which I’m hoping will make it easier to find the problem. I’ll add that I replaced the coolant temperature sensor since that’s supposed to be a common problem with hard starting. From what I can tell my car is stock.
What I’m trying to figure out is there something between the harness plug and the ECU, or where the wires go from the harness plug. I’m not finding a lot of info on this circuit in the wiring diagrams and I’m new at reading them. I have the 90 specific factory manuals and Haynes.
I’m hoping someone has run into the same issue and can share how they fixed it. I think my next step is figuring out if the circuit in the ECU is damaged? Or I’m totally barking up the wrong tree.
Fortunately the wiring in my car hasn’t been hacked up by previous owners which I’m hoping will make it easier to find the problem. I’ll add that I replaced the coolant temperature sensor since that’s supposed to be a common problem with hard starting. From what I can tell my car is stock.