Results 1 to 13 of 13

Thread: 2019 SS Knock issues

  1. #1
    Tuner in Training
    Join Date
    Sep 2019
    Posts
    13

    2019 SS Knock issues

    2019 2SS false knock.... I have been dealing with false knock from stock to after my flex fuel and tune and am about to install two new knock sensors but wanted to see who else has had this issue. Currently seeing about 1 degree WOT no matter timing or lambda and have desensitized with little help. I?m running e77 and working with Kyle from goat rope garage to troubleshoot. Hoping my sensors are crap and after replacing them it will help but looking for feedback from others about this and what they have done to stop it.

    Currently have rotofab cai,katech porter tb, awe track axle back and flex fuel kit.

    73256768_10215251873025526_8440746313108160512_n.jpg
    Attached Images Attached Images

  2. #2
    Tuner in Training
    Join Date
    Sep 2019
    Posts
    13
    attached a log showing the continued 1 degree knock
    Attached Files Attached Files

  3. #3
    Log your low side fuel pressure, if it's falling off that maybe your issue, does it do it on regular gasoline?

    KNOCK.png

  4. #4
    Tuner in Training
    Join Date
    Sep 2019
    Posts
    13
    I only run e now but prior I briefly logged and dynoed without e85 or any tune and still showed knock
    Attached Files Attached Files

  5. #5
    You have a blip of knock on that log, the first log shows almost 0 knock retard but a constant amount of "total knock" I've seen cases where the car is not reaching its desired fuel pressure and the injector pulse width is to high and it will do that. Log the fuel pressure on the low side, and fuel pump duty cycle. You can also have the car target a leaner A/f .88-.90 which will help.

  6. #6
    Tuner in Training
    Join Date
    Sep 2019
    Posts
    13
    What injector pulse with should I be conferenced with and where is fuel pressure low side? I have all channels for fuel open and don?t see anything with low available?

  7. #7
    Tuner in Training
    Join Date
    Sep 2019
    Posts
    13
    another log
    Attached Files Attached Files

  8. #8
    5MS, Low side fuel pressure is your normal fuel pressure from the pump, should be around 70psi or so. You are already logging your rail pressure.

  9. #9
    Tuner in Training
    Join Date
    Sep 2019
    Posts
    13
    Quote Originally Posted by ZincGT View Post
    5MS, Low side fuel pressure is your normal fuel pressure from the pump, should be around 70psi or so. You are already logging your rail pressure.
    I think I just found what you are talking about.

    if my fuel pressure requested is higher than what is being supplied would that cause car to pull timing?
    Attached Images Attached Images
    Attached Files Attached Files

  10. #10
    Tuner in Training
    Join Date
    Sep 2019
    Posts
    13
    Also, why are there times when it shows 0 fuel pressure!?

  11. #11
    Potential Tuner TobyB's Avatar
    Join Date
    Jun 2018
    Location
    Arlington Wa
    Posts
    6
    I had a coil take a slow shit that caused months of painful searching.
    03 Silverado | TSP 6.3l w/ 4l80e | RideTech

  12. #12
    Tuner in Training
    Join Date
    Sep 2019
    Posts
    13
    Static knock table solved my problems! Zero them out and poof no more false knock retard!

  13. #13
    Senior Tuner Frost's Avatar
    Join Date
    Jan 2006
    Location
    Richmond VA
    Posts
    1,783
    Quote Originally Posted by floridanick View Post
    Static knock table solved my problems! Zero them out and poof no more false knock retard!
    Interesting that it shows up under that umbrella..
    Steve Williams
    TunedbyFrost.com