# Ca18det knock above 7000rpm



## Pingu (May 22, 2003)

Hi

Even free revving in neutral (low load) the car makes a rapid detonation style sound and over 200 knock points on the SAFC-2 recording. This also occurs while driving.

Is it just my mines fuel chip that needs to be reburnet with different ignition or something , or are the valves floating or another drivetrain oddity?

I would have thought the low load situation of free revving in neutral (even though it builds boost) would be not a stress on the fuel system...

Any clue to ideas which its more likeley to be, as other ca18det guys might know...

Im replacing the fuelpump with a 550 hp capable one and larger flowing injectors , so that should eliminate some possibilities... Ill chuck in the stock chip and see if it does the same knocking sound also...

Anyone had this knocking sound? I would have thought even old worn valve springs still wouldnt float this early...


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## Marcus_S13 (Dec 6, 2004)

thats what is usually refered to in the car industry as a death knock...i think u could image y so if i was u i'd be very worried... have u had any oil surge problems??? cause it sounds like ur car may have been deprived of oil at high rpm resulting in the knocking sound...


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## Pingu (May 22, 2003)

I agree, since it happens when the car is under no load in neutral.

Ive changed the oil to a 10w30, which is what i usually use, before it was 10w40 and it was rooted.

I'll try again to see if it still knocks.


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## Marcus_S13 (Dec 6, 2004)

yeah it couldnt hurt, also check ur oil pump and maybe even check ur oil sump for damge (its quiet common for lowered cars to be damaging their sumps on speedhumps and so forth) cause maybe ur oil scoop in ur sump is unable to lift oil properly to the pump because of damage...ofcoarse without beening able to actually examine the vehicle just makes this all guess work... so hopefully that might help u sort out ur problem... keep me posted on ur progress... best of luck man


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