SES P0118 Engine Coolant Temperature [ECT] Sensor Circuit High Voltage..?
08-14-2009, 02:23 PM
#1
SES P0118 Engine Coolant Temperature [ECT] Sensor Circuit High Voltage..? What and where exactly is this sensor? My car has had trouble starting lately. It'll start up the first time when cold, and have trouble starting the 2nd time warm. It'll start, but struggle. My water temp gauge doesn't work at all after the 1st start.
Could the thermostat alone cause trouble starting? I'm guessing with this problem my fan won't come on, so I should be careful right?
Thank you everyone.
Could the thermostat alone cause trouble starting? I'm guessing with this problem my fan won't come on, so I should be careful right?
Thank you everyone.
08-14-2009, 02:44 PM
#2
TECH Senior Member
ECT sensor is in the head, right by #1. Check the connector/wiring or replace it, it's not expensive. The '98 has a three wire sensor - make sure you get the right replacement.
08-14-2009, 02:55 PM
#3
Hey man. My car is actually a 99, ignore my name lol. I just went and checked the connector.. from what i was able to see, the black and yellow wire were both okay. The plug didn't CLICK into place, but it had to be in all the way. What exactly is the sensor? I'm kinda lost here.. it sucks.
08-14-2009, 03:08 PM
#4
Hey man. My car is actually a 99, ignore my name lol. I just went and checked the connector.. from what i was able to see, the black and yellow wire were both okay. The plug didn't CLICK into place, but it had to be in all the way. What exactly is the sensor? I'm kinda lost here.. it sucks.
Its right out in plain site, just above the first spark plug on that head.
I have a 98....I know you have a 99. My car will not run without the temp sensor being plugged in or if it has failed. I'm certain that 99+ cars will have that problem too. Our PCM's are all NOT alike, they have minds of their own and all act differently.
Change the sensor.
.
08-16-2009, 09:15 PM
#6
LS1 coolant temperature sensor (98) (3-wire sensor: 2 for PCM, 1 for gauge) = 12551708
LS1 coolant temperature sensor (99-02) (2-wire) (AC-Delco #213-953) = 15326388
https://ls1tech.com/forums/3064646-post15.html
you got to special order this item as the dealership or pretty much any parts place. when you install it, dont over-torque it! wrap the threads in teflon tape and tighten to snug.
