Water Temp Sensor To Ecu

[RB20_ZED]

Hey ive had a faulty temp sensor to the ecu for a few months and finally bought a new one - car ran beautifully when i first installed it but now it seems to be having a the same problem (hesitates and backfires when cold).

I thought the new sensor had stuffed up... BUT if i unplug-replug the sensor before starting the car it seems to work fine... runs beautiful.

its as if the sensor needs to be reset or something...

any ideas what this may be? a voltage problem from the ecu? faulty sensor getting stuck? im really stumped but if there are no ideas im gonna have to rig up a switch to it.

[RB30-POWER]

disconnect the plug from the sensor, turn the ignition on and measure across the two pins with a multimeter, you have should measure 5V approx.

now keeping a good hold on the probes (or use small spade terminals if its easier) wiggle the wiring harness and make sure you always have 5V, if it fluctuates or you dont have 5V you have a broken wire somewhere or ecu is root.

[RB30-POWER]

by the way forgot to mention the earth for the water temp is a common earth (ecu pin 30) for throttle position sensor and exhaust temp sensor as well.

because its a conversion, if you have done something funny with the exhaust temp sensor wiring like wire it to 12v it might be causing all the problems, because there is no ground for the sensor to go too.