I don’t have a data log recording at hand, however I believe I caught some spark retard under higher Load values/ under boost.
On the one hand, if the knock sensor is doing its job then great: just back off the spark advance.
On the other hand, I wonder if it could be false knock being detected.
Is this time to hit the rolls?
Is there a way to validate the knock sensors calibration?
How could one adjust the knock sensor calibration?
Thanks
Calibrating Knock Sensor(s)
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m-barans
- Posts: 93
- Joined: 2021 Feb 16, 23:09
- Location: Lafayette, Oregon US
- Vehicle Information: 2003 Mercury Marauder 300A with new stock bore IRON 4.6 block, Manley crank, Manley H-tuff h-beam rods, CP pistons with stainless rings, ARP head studs, GT500 lash adjusters and rollers, D series cylinder heads, VMP GEN3R 2.65 L TVS blower, 80 lb/hr FRPP Siemens Deka injectors, HPX slot 100mm MAF, coyote mustang fuel pump with Holley 60 psi filter/regulator return at pump, Stainless works long tube headers and complete exhaust, Moates quarter horse and TunerPro RT with support from Decipha, RZASA strategy.
2001 Ford Lightning SVT F-150 stock engine w/ inlet ported M112, GT500 rollers, ARP head studs, metco quick change upper pulley with stock sized upper, K&N intake system, bassani SS exhaust system from the stock manifold flanges back. 4x4 trans oil pan. SSBC big brakes 14” up front. Work/Street truck. My “next to build” with trick flow heads (before extinction) with h-beams & cobra jet crank (sitting in tool box) and proper pistons. Next up after the marauder is dialed in.
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decipha
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- Vehicle Information: Work Truck
'25 F-150 5L
Re: Calibrating Knock Sensor(s)
youll need a secondary way of detecting knock in order to determine if its knock or not
some folks mount a secondary knock sensor to one of the heads and run it to an amplifier with headphones and listen that way
as for calibrating it, enable the decipha knock patch and dial in the knock threshold table.
if the table isnt linear then take the non linear areas and kick up the gain at that area.
if the gain is up and the threshold is up and its still detecting false knock then change the offset in that area to bring the threshold and gain back in line to a linear range
the knk_ad2tst or spkad or whatever its called will show how much spark is being added or retard from the knock sensor(s). Adjust the threshold so it doesnt runaway dumping in too much spark and so that it doesnt yank all of it out.
Youll get the hang of it after you tinker a few times.
if you download my high performance 87 octane marauder tune youll see how i have the knock sensor dialed in for my 03.
Keep in mind the threshold will need to be dialed in on each and every vehicle. My marauder is entirely different than 4 other stock marauders i tried it on. Mine for whatever reason was the least sensitive out of all marauders ive done for whatever reason. Mine also has the most miles too but miraculously runs and idles smoother than all the others as well for what its worth.
some folks mount a secondary knock sensor to one of the heads and run it to an amplifier with headphones and listen that way
as for calibrating it, enable the decipha knock patch and dial in the knock threshold table.
if the table isnt linear then take the non linear areas and kick up the gain at that area.
if the gain is up and the threshold is up and its still detecting false knock then change the offset in that area to bring the threshold and gain back in line to a linear range
the knk_ad2tst or spkad or whatever its called will show how much spark is being added or retard from the knock sensor(s). Adjust the threshold so it doesnt runaway dumping in too much spark and so that it doesnt yank all of it out.
Youll get the hang of it after you tinker a few times.
if you download my high performance 87 octane marauder tune youll see how i have the knock sensor dialed in for my 03.
Keep in mind the threshold will need to be dialed in on each and every vehicle. My marauder is entirely different than 4 other stock marauders i tried it on. Mine for whatever reason was the least sensitive out of all marauders ive done for whatever reason. Mine also has the most miles too but miraculously runs and idles smoother than all the others as well for what its worth.