Ok so i have a weird problem with my stock temperature gauge.

I would go up to the car in the morning, and the gauge shows the engine is warm (like the last time I drove the car). I put in the key, turn it to ON position, the gauge still shows warm. After a few seconds, maybe more sometimes, the needle drops to cold. If I try to start the engine while it's showing warm, it will run like crap.

I'm guessing the sensor is bad? Does the gauge drop to cold when you take your key out? I seem too recall that's how it worked before, not sure though..

 

Hmm, I think mine stays on with the key out. Check the wiring to the sensor, this one breaks a LOT.

 

Thanks, I'll try that.
Good to know it should stay on, maybe sensor just gets stuck in the warm position or something (if it's not the wiring)

 

sounds like your gauge is sticking and not un-sticking until it's powered. Mine drops down when I turn off the car.

The crappy starting could have something to do with your fuel tank's check valve.

 

mine drops like a stone when the key is taken out.

 

Could be the sensor also. And the bad startup could be because it is reading the wrong temp and using the wrong fuel mixture.

 

The ECT sensor and the ECT sender are too different units. the ECT sensor goes to the ECU only, the ECT sender goes to the gauge only.

 

Hm, there are two sensors, one for the ECU and one for the gauge?

I was thinking what ericy said, wrong temperature = wrong trims, if I let the gauge drop first it starts and runs with no issues.

Didn't have this problem happening today though.. Still have to check the wiring

 

same here mine drops like a rock after key is taken out

 

There are 2 sensors in the car.
The one is thiner then the other.

1. The thinner one is for the guage(Single pin).

2. And the other is also a temp sensor(Double pin).
That is like a cold start sensor.
And also works your fans.
This is what i experienced when selling these parts to mechanics.


So if the thicker one(2nd) one is not functioning well it wont run rich when the car is cold.
Which probably makes it run like shit.


Details of sensor

PART NO.39220-22010 SENSOR ASSY-COOLANT TEMPERATURE