can heavy engine load cause KR?
11-10-2003, 07:40 PM
#1
can heavy engine load cause KR? ok here is the deal, 6th gear at 50 and i gave it a good bit of throttle, got 1* or KR. just wanted to see if it was normal to get KR when the motor bogs or is put under heavy load in a high gear....pretty much too much throttle for the speed in that gear. thoguht i heard it was normal somewhere else just wanted to check.
got stuck in some traffic and forgot to down shift lol
11-10-2003, 08:54 PM
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yes this will cause KR. any loading of the motor such as a good deal of extra weight, serious wind resistance, even a taller gear will increase the likeliness of spark knock. Essentially anything that will not allow the engine to freely rev will be nearing spark knock, and anything that decreases load on the motor will allow for more timing and the possibility of more power.
Jeremy
Jeremy
11-10-2003, 09:59 PM
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The engine should pull timing with load (manifold
pressure). If your timing is too advanced the high
MAP (hence high cylinder filling and cylinder pressure)
end of things will expose it. Because the PCM has a
reaction time to things, you can get far enough into
spark knock on a throttle or load transient to set off
knock detect, and KR means the PCM is on the job
but a little late or a little short (which one, you can tell
by whether it goes away or sticks around).
pressure). If your timing is too advanced the high
MAP (hence high cylinder filling and cylinder pressure)
end of things will expose it. Because the PCM has a
reaction time to things, you can get far enough into
spark knock on a throttle or load transient to set off
knock detect, and KR means the PCM is on the job
but a little late or a little short (which one, you can tell
by whether it goes away or sticks around).
