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Guest Message by DevFuse

- - - - -

ECS Light VS. Temp Sensor

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6 replies to this topic

#1 TheSubaruJunkie



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  • Sacramento

Posted 18 January 2004 - 09:29 PM

I installed an aftermarket coolant temp guage, and it came with its own manual temp sensor. I had to remove the stock sensor and unplug it of course. Now when i drive the car for more than 10 or 15min, my ECS light comes on. Ive plugged the plug back into the stock temp sensor, and that solved the problem for a while, but now its back.

Is there anyway to bypass this?


#2 baccaruda



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Posted 18 January 2004 - 09:35 PM

maybe the wiring harness is crunchy? i had to rebuild the plug for the CTS on my car.

#3 GLCraig



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  • Canby @#$% Oregon

Posted 18 January 2004 - 10:34 PM

First check the codes from the ECU to see if it's something else. If it is a bad sensor code, try connecting the WB to a 42ohm resistor and ground the other end of the resistor. This should fool the ECU in thinking that the coolant temp is 187F.

#4 NV Zeno

NV Zeno

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Posted 18 January 2004 - 11:31 PM

That's exactly the symptom my car had, way back when it only had high-100K miles.

As I recall, driveability was not affected, but the temp sensor was the component that was found to be malfunctioning.

#5 GeneralDisorder


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Posted 18 January 2004 - 11:33 PM

Um - for one thing you really should put that sensor back in - that's part of the feedback carb's sensor system, and without it, you are unlikely to be able to pass CA emissions. I can almost guarantee that your ECS light is caused by your removal of the sensor - the ECU is running in "open loop" mode because it thinks the engine is never warming up.....

I had to replace that sensor on my wagon last year before I put on a weber..... same problem - dirve for 15 minutes and the light comes on.


#6 Hondasucks


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Posted 19 January 2004 - 04:50 AM

yeah Junkie, there are two sensors in that thinger, one of them feeds the gauge in the dash, and the other one feeds the computer. There are two options:

One: Remove the thermo vacuum valve that is on the front side of the manifold and plumb the two lines that are connected when the car is hot together, and put the sensor there (what I did on my hatchback since that valve had broken off)

two: Get some Tee fittings and make a Tee junction like this:

old sensor ------------ new sensor





#7 TheSubaruJunkie



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Posted 19 January 2004 - 04:56 AM

Its not the sensor thats bad, my guage is bad. If i put the stock sensor back in, i have no idea how hot my engine is running.


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