Results 1 to 6 of 6

Thread: P2176 when ECT is 204F+

  1. #1
    Tuner in Training
    Join Date
    Jul 2019
    Location
    N of Houston TX
    Posts
    17

    P2176 when ECT is 204F+

    IF.... this successful since it will be my first post....

    I'm totally lost here and NEW to the tuning world....

    2007 Corvette, LS2, Whipple 2.9 SC, upgraded MAP, upgraded MAF, Nick Williams 102 TB for boost applications, new 160F T-stat, NEW coolant temp sensor......and can provide any other info that may be needed to help in solving my issue.

    Any time I drive the car and stop anywhere when the engine coolant temp (ECT) is 204 F and above, when ever go to restart the car, I get a P2176 code and MIL....... the car goes into "reduced power mode" and seems as if it's running on 4 cyl.....

    I have found that if I carry my Code Scanner with me all the time, I can start the car and while it's limping along, I can do an "erase" of the code and the car will clean up and runs normally and I can continue on my way. Secondly, I can simply "wait" until the car cools down and it starts and runs normally and continue on my way......

    Lastly, I just tried it..... When I know the car is hotter than 204, I can simply unplug the coolant temp sensor, and the car will start and idle/run normally but will light up the DIC (driver info center) with the message that the car is HOT and to turn off the AC.

    I can post the current tune in the car if that helps......

    Thanks in advance....

  2. #2
    Advanced Tuner
    Join Date
    Apr 2017
    Location
    Meridian MS
    Posts
    478
    Throttle Learn

    Description
    The engine control module (ECM) learns the idle position of the throttle plate to ensure the correct idle. Anytime the throttle body is cleaned or replaced, the ECM must learn the new throttle position. The idle may be unstable or a DTC may set if the throttle position is not learned.

    Conditions for Running the Throttle Learn Procedure
    • DTCs P0101, P0102, P0103, P0107, P0108, P0111, P0112, P0113, P0506, and P0507 are not set.
    • The engine speed is between 450-4,000 RPM.
    • The manifold absolute pressure (MAP) is greater than 5 kPa.
    • The mass air flow (MAF) is greater than 2 g/s.
    • The ignition 1 voltage is greater than 10 volts.

    Throttle Learn
    Important: Do NOT perform this procedure if DTCs are set. Refer to Diagnostic Trouble Code (DTC) List - Vehicle .

    Start and idle the engine in PARK for 3 minutes.
    With a scan tool, monitor desired and actual RPM.
    The ECM will start to learn the new idle cells and Desired RPM should start to decrease.
    Ignition OFF for 60 seconds.
    Start and idle the engine in PARK for 3 minutes.
    After the 3 minute run time the engine should be idling normal.

    Important: During the drive cycle the check engine light may come on with idle speed DTCs. If idle speed codes are set, clear codes so the ECM can continue to learn.
    ⇒ If the engine idle speed has not been learned the vehicle will need to be driven at speeds above 70 km/h (44 mph) with several decelerations and extended idles.
    After the drive cycle, the engine should be idling normally.
    ⇒ If the engine idle speed has not been learned, turn OFF the ignition for 60 seconds and repeat step 6.
    Once the engine speed has returned to normal, clear DTCs.

  3. #3
    Tuner in Training
    Join Date
    Jul 2019
    Location
    N of Houston TX
    Posts
    17
    Thanks blindsquirrel...... I have tried the relearn multiple times.........

    the problem I have is only happening when my ECT is above 204 degrees.....

    When I drive the car and stop anywhere and the coolant temps are above 204, I already know that I will have to clear the code so that I can continue on my way...

    I am certainly no tuner.....but it seems as if the throttle needs more "time" to go through it's processes to learn its positions....being the 2007 Corvettes are "push button" starts, I can't simply turn a key and wait for a few moments while the car goes through any start up procedures ......

    Hopefully someone will have a suggestion that I haven't tried.....

  4. #4
    Advanced Tuner
    Join Date
    Apr 2017
    Location
    Meridian MS
    Posts
    478
    This sounds like a mechanical condition (not necessarily a defect) with the throttle body that the ECM doesn't know how to deal with. Have you contacted Nick Williams? I'm sure you are not the first one using their TB to see this, they will know what it takes to solve it.

  5. #5
    Advanced Tuner
    Join Date
    Apr 2017
    Location
    Meridian MS
    Posts
    478
    Ignition ON Engine OFF mode

    This mode is used to have all modules powered up and communicating on the serial data line. In order to achieve this mode the customer must have a valid key fob within the passenger compartment of the vehicle, the brake pedal depressed, and the transmission in Park or Neutral. Once that criteria is met, the customer must press and hold for 5 seconds the ACC/OFF portion of the Start/ACC/OFF mode button. The vehicle will power up with the engine OFF. A low transmitter battery or radio frequency (RF) interference from aftermarket devices such as 2-way radios, power inverters, cellular phone chargers, computers, etc. may cause a system malfunction. High RF traffic areas, such as gas stations which use pay-at-the-pump RF transponders, may also cause interference that could lead to a malfunction.
    It doesn't mention anything about how long it'll stay in that mode without intervention but I'm sure there is some kind of timer monitoring things. How long can you get it to stay 'ON' for when putting it in that mode?

  6. #6
    Tuner in Training
    Join Date
    Jul 2019
    Location
    N of Houston TX
    Posts
    17
    I appreciate your time, input, and suggestions........

    I have not talked to Texas Speed (who I purchased the NW 102 from) or Nick Williams.....

    That being said, I don't believe it's a TB issue.... after MORE trial and error stuff, I have pin pointed the temperature that the car seems to have the issue..... 208F on the DIC and the car will start normally and idle, 210F on the DIC and the car will not find it's idle (P2176) and go into reduced engine power mode.

    Secondly, it doesn't matter what the ECT is 160-225+...... I can unplug the coolant temp sensor on the engine and start the car. It will come up to idle and runs normally...... I can plug the sensor back in and drive away..... NO issues.....BTW, the coolant temp sensor is NEW (O'Riellys), Water pump is NEW (AC Delco), T-Stat NEW (Lingenfelter 160)

    It may have been an "induced" code.....but while the car was limping along in reduced power mode, I depressed the gas pedal and it did set a code of P0606....... that was erasable........

    Still lost here..... hopefully there are other suggestions out there.....

    2007 Vette.......... stock E38 ECU..... A6 Trans.......