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knocking after tune

1854 Views 47 Replies 14 Participants Last post by  Grabber523
has anyone encountered this problem? after i installed my kb tune i needed to change back to stock, and after reinstalling the kb tune back in i have a severe misfire / knock. after this i sent the sct back to kenne bell, they said everything was fine with the tune and even sent me a new sct. the car still sounds like a jackhammer but will not display a code. any ideas?
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yea, i will get some pics up as soon as i get her back and clean her up. shes been in my dusty garage with no cover for about 4 months while i've been puttin the kb on gettin the blown rear fixed.
Took me several tries to load my tune. Had to flash back to stock, reset the ECU by pulling and reinstalling the negative battery cable, then re-installing the KB tune. Works perfectly.
thanks for the advice but i tried that a couple of times with no luck. nothing like having a day in feb with 60 degree temps and a new kb and not being able to drive it.
Have a similar issue ,car ran fine at first but had a sound in the exhaust that was unfamiliar at idle.everything was good for a little bit and then the shakes at idle.Changed plugs, stops for two days then start again.Funny part the car drives fine but idle is not smooth all the time especially after low speed driving.KB is clueless dyno tune for that bitch.I have had it and if that doesn't work then i am screwed.Did you purchase the non intercooled kit also before you waste money take to the dyno guys it might be something different than what you think.
my car cannot even be driven, the knock is so bad it sounds like a jackhammer! i had a similar problem before when changing tunes but got it to go away with the stock tune sent to me by bamma that would not go away with my stock tune from car. why i have no idea! so i dont think its the kb tune. i am tring to get a custom tune but everybody out here is backed up until may!!! i haven't driven the car in months and no way can i wait till may. i just think I'm cursed, every time i do something to the car it goes wrong. F%#K :mad::mad::mad::mad::mad:
i might just take it to ford and let them put it on the big ford computer. i'd rather take it somewhere and get custom tune but i just can't wait that long.
Did you try disconnecting the battery for 15 minutes, and then starting from scratch again? I haven't done this myself, so I don't know if it holds any truth, but I've seen other guys saying that doing so resets things in the PCM.

It's worth a shot for what it takes to disco the battery for 15 minutes.
Yah I would just leave battery unpluged over night. I used to do that on my old car. The juice is drained out of the Comp.
yea tried that too. i waited couple of hrs., waited overnight, waited over the weekend and nothing. which leads me to think it much deeper than just the tuner.
What's your plug gap?
they are at the stock plug gap, i don't think it blowout because it's a problem at idle.
Call your tuner or SCT to fix the problem. If its a mechanical problem they will not be able to fix it. does it detonate right after startup? Can you datalog how much timing there is? Its really weird that it knocks at idle. With such low cylinder pressures it can handle huge timing and lean AF without knocking. Can you shoot a short video or describe the problem with lots of detail? If it starts knocking get out of the gas or turn it off if you are already off the gas. Have you checked the oil and coolant?
i already checked the oil coolant etc... i don't think its detonation either, i just think something in the ecu is throwing the timing way off and its not as simple as just taking timing out.
All those wires you had to splice out and rewire you should check them.the computer is relocated and have to be plugged back in.If i were you i would go over the install piece by piece it took a long time to take apart and put the blower on but checking every detail now that the install is done is not hard.Check everything,make sure you matched the right wires because kb instruction booklet is an 05 model and some of those wire colours changed.Check your vaccum lines make sure everything is right and get a fresh set of hto and when you have checked every detail reload kb tune and see what she does.You might as well do it.And i am going to tell you this Ford is just going to take your money and not fix your problem,they will look at your car like its from another planet and when it comes to blower once everything is sealed tight matched right,it becomes a tuning issue and ford can't tune your car,i speak from experience.
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Find the nearest shop that deals with these things if you can't figure it out,call your insurance or roadside assistance tell them your car has broken down and you managed to push it back home and you need to have it towed.Call a shop outside your area do what you have to but don,t wasted your time with the dealership,they will just piss you off and wouldn't warrant the work.Because of your mod.Choice is still and always yours.
i appreciate the help guys but I've been struggling with this for too long. Ive exhausted all my resources, time for the pros to handle it.
don't know if anybody is paying attention to this anymore but the shop i took my car to found the problem. turns out it's not a tune related problem after all, it actually was a bad cam chain tensioner and some other part that i forget the name of. an expensive coincidence figuring that ford wouldn't fix it because of the kenne bell, so i have to pay somebody to do something that ford should have warrantied.
Did the car have this issue before?Ford doesn't care, they would use any excuse to brush you of.You said you didn't even drive the car,was the problem there before or you didn't feel it until you did the install.
yea, it had the problem before but went away, i guess it was just coincidence that the chain tensioner Finally gave up around the same time the kb went on. the install of the kenne bell is just too involved to return it to stock to get it repaired under warranty so i took it to big daddy performance here in nj.
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