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knocking after tune

1856 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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thanks for the reply guys but the problems not the kb tune because the first time i loaded the tune it worked fine. its only when i returned it to stock then back to kb that it started knocking, i tried returning it to factory stock and the same thing happens. nothing like having a new kb on your car and not being able to drive it, especially when its nice and sunny here in southern nj. i tried to go onto the sct troubleshoot forum but it is saying that its down for updates since 11/28/07.

no, i just installed the stock tune and left the blower on just to see if it would idle regular which it did not. i also tried the reset the ecm thing with no luck. the problem must be with the ecm or the x cal.
im pretty sure there are no vac leaks i was through with install and went back over everything a couple times after. to answer the other question i only ran the car for a couple seconds at idle a few times, im a diesel mechanic so im pretty auto inclined.
oh, by the way my a/f meter is reading very lean which i think is caused by cylinders misfiring due to computer. keep in mind that the tune provided by kenne bell was running well at one point before i returned to stock and then back to kb. i fear that i might have to send the car to ford to get the ecu checked by the dealers computer. i already called ford parts for new ecm which costs $600+ alone not including the cost to have ford flash the new ecm.
i just think this goes well beyond just a simple a/f problem, i contacted sct and they said it probably a stuck frame in the ecm, which is not changing paremeters in ecm when being tuned. sct says to take it to get a custom tune or to ford to check the ecm. not looking forward to the bill for that one.
i gone and done it, i'm taking it to big daddys performance in lakewood nj for a custom tune and perhaps cams, not sure i have to talk to him about it. i'm tired of playing around with it and need professional help. thanks guys for all the advice you have given me i appreciate it.
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.
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.
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.
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.
they are at the stock plug gap, i don't think it blowout because it's a problem at idle.
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.
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.
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.
no i didn't have cams put in because im paying out the ass to get the rest of the problems fixed. i think im going to do a short block over next winter so im going to do cams and some other things then. yeah oddball every time i do something to my car it inter fears with something else ive done. i guess thats what happens when you f**k with a brand new car as much as i have.
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