Results 1 to 4 of 4

Thread: Keep getting P1516 and reduced power

  1. #1

    Keep getting P1516 and reduced power

    This started happening a few days ago and only seems to happen after going WOT in 4th gear. As soon as I let off the gas a few seconds later it goes into reduced power. I attached the log I did when it happened and there seems to be some strange things going on in the TPS reading at 20 seconds. I have never seen the value go below 20% like this.I will attach my tune as well. The air quality sucks here right now it is hot and humid at night. The KPA is low since I am up around 2000ft but a few days ago I was down by the ocean and it was seeing 100+ KPA but got a lot of knock retard and I hear it ping. I run 91 octane here in California and 32oz of Torco to try to help with Knock but it was getting upwards of 24 degrees of timing and usually I only see 21.5 up near where I live.

    Car is 2007 ZO6

    Mods:
    Ported heads
    11.5 compression with 8.55 Dynamic
    Ported FAST intake and Nick Williams 102mm TB
    Halltech MF 105S CAI - MAF forward style - Also opened up the NACA Duct as Jim Hall suggested
    Cam is 236/246 112+4 639/657
    Pfadt 1 7/8 Headers and catted xpipe
    GZ Vaccu Pump
    Stock injectors
    Stock MAP sensor

    The car was tuned on the dyno to 12.8:1 AFR

  2. #2
    Advanced Tuner
    Join Date
    Jan 2008
    Posts
    242
    The actual throttle position does not match the predicted throttle position for greater than 0.2 s.

  3. #3
    So where do I need to change this? I am no tuner and the guy who does my tuning is hard to get on the phone and nail down his time to look at logs and make adjustments. I can do it if I know where to go to make these changes. I was poking around in the tune and saw there is a place in the airflow section that has an area called "reduced power" but says to change at your own risk as it may cause permanent damage to PCM.

    Would increasing the Engine Diag-TPS Sensor P2101 values help with it going into reduced power mode? I also see the ETC Area scalar is set to 3,800 but not sure if it is right. Also in the effective area it shows Max set to 8191square millimeters but isn't 102mm TB actually 7147mm2? Maybe this has no impact on the error though as the min value is set to 0.
    Last edited by twistedpixels; 07-27-2014 at 02:22 AM.

  4. #4
    anyone have any other ideas abut this issue? I tried setting area scalar to the values Greg Banish suggested but it wouldn't start so my tuner obviously changed a lot of things with airflow maybe? It started doing it under normal driving as well. I was able to get my original tune back from the first tuner who did my car when I never had this issue and drove it hard for 30min and it never triggered the code but I saw that in his tune the ETC area scalar is set to stock I think which is 4725. I will attach his file as well.