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hi brains trust,

im having an issue with false KS counts.

Im getting a constant ~200 count (tunerpro5) using the 808 ECU

this leads to a constant 12 deg retard.

There is not one component in the electrical side that has not been replaced over the past 12 months.

Im thinking that im getting electrical interference in the system?


If i disconnect the KS i get a 6 deg retard (which is better drivability than 12 deg!!, but interestingly with the KS disconected i still get a constant knock counts of ~ 200!!


The knock count is across ALL engine operating conditions be it, idle, WOT or over run!

Loom earths are in the correct positions etc (loom has also been changed out)

Any ideas which way to start looking?

What engine is the 808 running?

this is an Ecotec engine in a 4x4, and its using my $12P 808 ecotec bin file from the custom tunes thread, and he is also using a VN/VP knock sensor.

Ah ok. Well that stuffs my ideas up then! I was thinking ecotec sensor on 808.

What's IAT showing?

Any data logs?

an earlier log

Can't spot any issues there but it is very similar to my own VN wagon when it had a knock sensor that had, had the dick. Someone had over tightened and it was shorting internally.

Turn the knock sensor off in the tune and try it?

thanks gareth,,

my thoughts as well. although im bit uncomfortable about turning the KS off long term?


This was with a new sensor, and then i tried a second hand one which looked good for a little while then threw the same knock count.

I was also thinking maybe an aftermarket radio GPS may be causing an issue??

I always disable sensor, they are useless on the delco for the same reason of ample false knock and also failing to detect real knock.

I just tune a safe spark table and call it done. Best way is on a dyno with knock headphones, that way you know it will be 100% safe. Only thing to be mindful is ecotec have fragile brittle pistons and easily break from knock.

yes, im very happy with sam's tune it works very well for me its just this false knock count thing did not occur when first converted! Its happened later but i just cant work out what changes i have done that may have induced it!!

The only obvious changes that i can remember is the quieter exhaust from the 'y' piece back and the GPS radio rear camera

rgds