fernando.

I just drove my S2 home tonight and I must say I'm super impressed by this car, haha. The engine was swapped for the same F20c due to a miss-shift, the car runs amazing but the temp gauge doesn't work. I drove the car 30 miles home and the gauge only had one bar the whole drive home. Any ideas what this could be?

bbss2k

I had the same issue and ironically, my engine was replaced for the same reason before I bought the car. Replace the temp sensor. It's on the back of the intake manifold. Got mine from Honda for $25

fernando.

That what I figured it might be, maybe they hit the sensor off the firewall or something and damaged it.

fernando.

Ok, well here they want $60 for the sensor so before I go and replace it I just want to make sure that is the problem. I used a volt meter and the plug had 4.97v which from what I'm told is normal. I asked at Honda and they told me "Well if the ECT is pooched then the motor will run like shit because the ECU won't know the temp of the motor and it'll keep it in open loop and also throw a code" ...this true?

Stratocaster

The temp effects the tune. So lacking a temp sensor will be a problem.

fernando.

I'm stumped, there's 4.97v going to the sensor, I have no CEL, I'm not 100% sure if the fans are kicking in though. Unless this is an issue between the ECU and the cluster...

vividracing.com

Are you testing the sensor at the ECU, or at the sensor? Test it at the ECU, so you know what the signal looks like when it gets to the ECU. You might be getting a bad signal @ the ECU, but a great signal @ the sensor.

fernando.

Nevermind, figured it out. Wire was pulled out at the ECU plug.

lilsharky

do you know the P/N to the sensor? Was it hard to replace?

fernando.

The problem wasn't the sensor. I pulled off the ECU kick panel and found the yellow/green signal wire for the ECT to the cluster was pulled out of the ECU plug.