Engine temperature sensor(s)

[MartinClan]

The 325 engine I am using in my Sportster has two engine temperature sensors, one with a brown top and one blue - both mounted in the thermostsat housing.

The question is are they BOTH used by the engine management unit - or can I replace one with a temperature sensor for use with the aftermarket temperature gauge I am using?

Cheers

Robin

[GreatOldOne]

You can swap the brown one out IIRC - It's the blue one that feeds the ECU.

[Patrick]

Yup blue one is for the ECU brown one is for the gauge.

If you have idle or running problems with the engine very often its the blue sensor at fault :)