Results 1 to 4 of 4

Thread: Help - Engine Coolant Temp gone out twice - 2004 Silverado - Stock 5.3

  1. #1
    Potential Tuner
    Join Date
    May 2020
    Posts
    3

    Post Help - Engine Coolant Temp gone out twice - 2004 Silverado - Stock 5.3

    Greetings Guys,

    Needing some assistance. 2004 Chevy Silverado, Bone stock, added Electronic Fans. No issues on several drives, but after almost a week, Monday/Tuesday, idling in my yard, A/C on, the Coolant Temperature Sensor went out. RPM's jumped slightly, of course the fans kicked on continuously. I replaced the Coolant Temperature, and today again, idling, with the A/C on, Coolant Temp Sensor went out again.

    I've attached the latest tune, and only modifications are to fans, PE.

    51820 2224.hpt

    Any suggestions on this?

  2. #2
    Senior Tuner
    Join Date
    Mar 2011
    Location
    Ripley, MS
    Posts
    1,865
    It's not likely that both sensors are bad. It's very likely that there is an issue with one of the wires. There is a sensor ground and a signal wire on the sensor. Make sure that the wires are in good shape and the terminals are properly crimped.

  3. #3
    Potential Tuner
    Join Date
    May 2020
    Posts
    3
    Solved: After remembering this issue did not start until the fans were installed, I finally did an indepth diagnosis. Was able to catch the engine coolant temp in a moment where it went out: I ungrounded each fan to see if there was an inherent draw on the charging system. After ungrounding one fan, it seemed to have alleviated the issue, but it quickly returned. I then ungrounded both fans, the issue persisted. Only offender left was the ECU, I tapped it, and it had an immediate effect on the idle, and engine coolant temp sensor. I removed the cover to the ECU to find that when I reinstalled one of the harnesses it did not fully seat, or make good contact on one side. Seated it properly, and have not had any further issues. Thanks for your reply.

    Quote Originally Posted by kevin87turbot View Post
    It's not likely that both sensors are bad. It's very likely that there is an issue with one of the wires. There is a sensor ground and a signal wire on the sensor. Make sure that the wires are in good shape and the terminals are properly crimped.

  4. #4
    Potential Tuner
    Join Date
    May 2020
    Posts
    3
    Solved: After remembering this issue did not start until the fans were installed, I finally did an indepth diagnosis. Was able to catch the engine coolant temp in a moment where it went out: I ungrounded each fan to see if there was an inherent draw on the charging system. After ungrounding one fan, it seemed to have alleviated the issue, but it quickly returned. I then ungrounded both fans, the issue persisted. Only offender left was the ECU, I tapped it, and it had an immediate effect on the idle, and engine coolant temp sensor. I removed the cover to the ECU to find that when I reinstalled one of the harnesses it did not fully seat, or make good contact on one side. Seated it properly, and have not had any further issues. Thanks for your reply.

    Quote Originally Posted by kevin87turbot View Post
    It's not likely that both sensors are bad. It's very likely that there is an issue with one of the wires. There is a sensor ground and a signal wire on the sensor. Make sure that the wires are in good shape and the terminals are properly crimped.