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Pfc Read Knock Level Of 79

ahh 33 s2

By ahh 33 s2,
in General Maintenance

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ahh 33 s2 Mentor

ahh 33 s2

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Posted

i just checked all my levels on my hand controler. after getting the back out around a corner and hitting the rev limter in second my knock level read a max of 79.

my previous highest knock level was a 19 again when hitting the limter.

i had to double check what i was reading because it seemed a lot high

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https://www.sau.com.au/forums/topic/168815-pfc-read-knock-level-of-79/
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Posted
Posted

could be a dodgy batch of fuel? boost spiking? ambient temp when attempting the sideways action?

i didnt actually see a question in there but im assuming you wanna know why it was knocking so much? personally, i wouldnt be too worried about it as long as your not doing it 24/7, even then 79 isnt too high. from memory the PFC cuts in to warn you at about 60 which is well short of doing any damage

ahh 33 s2 Mentor

ahh 33 s2

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yeh sorry mate.. what i was asking is firstly could this be a correct reading and secondly how bad of a reading is this.. the engine light did come on how ever when it happened. injector duty was below 90% and a/f was 5110 but i do have a Z32 afm so i dont think thats the prob.

what is a reading to be worried about

noone Experienced

noone

Posted
Posted (edited)

engine light typically set at 60 knock and anything above that is a concern if it is only happening at the limiter easy fix dont hit the limiter

unless you see it all the time I wouldn't loose to much sleep if its pretty regular ask your tuner he might be able to put more fuel or less ignition at the limit point

might help?!?

Woulda thought 90% injector duty is pushing it too much too?

Edited by noone
  • 2 weeks later...

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