legacycentral bbs

Short version: Can I use pretty much any 90-94 NA ECU in my 94 5MT?

Long version: The car was throwing a CEL for the coolant temp sensor and the fans would kick on as soon as the ignition was put into the "on" position. I checked the sensor, it seems okay since it has the right resistance. I also had about 5 volts at the wires that run to the sensor. I also checked the wires that run from the sensor to where they run into the ECU. Everything checked out. This makes me think that the problem must be somewhere within the ECU. Any thoughts?

Thanks,
Barn

Replace the temp sensor.

ericem wrote:Replace the temp sensor.

+1


Even though it 'checks out,' there could still be a problem with it. A temp sensor is about $30. Much cheaper than an ECU.

I did put a new one in there, same problem.

Was it an OEM temp sensor?

All the wiring came back with 0 ohms resistance?

If all that was good, I'd suggest checking to make sure you don't have any air bubbles in the cooling system, and then from there, I'd suggest performing a D-check on the ECU, and then a reset with the black & green connectors.

Info on how to do this is on my site
www.surrealmirage.com/subaru/engine.html