Burst knock???
#5
TECH Fanatic
iTrader: (1)
Mine do it as long the car is in open loop but the engine is still warm (like after a 10 min stop, fuel cell = 20). Watching the wideband I see AFR around 16:1 during very short times and the ping is also audible.
As soon the PCM switches to closed loop it's fine, no more KR (?????)
As soon the PCM switches to closed loop it's fine, no more KR (?????)
#6
TECH Senior Member
iTrader: (33)
phil, are you trying to get rid of actual knock or burst knock? you said burst/tip in. burst knock is its own parameter and wont show as regualar knock but then you get the tip in knock if the burst doesnt pull enough timing or the o2s dip lean right at you jump on the gas. you can reduce the burst knock timing pulled if that is too high. if the ve is set up right and you get tip in from what i have seen on take off is a lot of it is related to wheel spin or bogging and going rich, somewhat of a false kncok.
#7
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Burst knock retard is a predictive pullback, meant to
cover tip-in ping. They kind of go together but they
are different issues. Burst knock can be applied too
easily (like on trucks). That saps power. Tip-in ping
is another issue, most probably speed density tune
being over-lean or the PE enables being too far out
vs the cylinder pressure and the applied timing (where
the motor starts to need enrichment).
Tell us a bit more about what it is you're seeing and
what you want to do here.
cover tip-in ping. They kind of go together but they
are different issues. Burst knock can be applied too
easily (like on trucks). That saps power. Tip-in ping
is another issue, most probably speed density tune
being over-lean or the PE enables being too far out
vs the cylinder pressure and the applied timing (where
the motor starts to need enrichment).
Tell us a bit more about what it is you're seeing and
what you want to do here.