Sources of knock (false?)
#1
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Sources of knock (false?)
While I still had some toluene on my gas from Friday, i got some scanning done. The toluene should have given me ~95.5 octane. Scans just now around town and on the highway revealed similar amounts of knock retard as with 93 octane, at most, I saw 5 degrees of retard. However, going 70 mph on the highway, floor it so it shifts to second, I saw 17 DEGREES for a moment, dropped to 11 then dropped off.
Now I think I have some false knock. What are the sources of false knock retard on a Series I L67?
Now I think I have some false knock. What are the sources of false knock retard on a Series I L67?
#6
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I know you said false but,
Oil. I'm convinced that my heads were leaking oil causing predetonation.
Does you car loose a noticeable amount of oil between oil changes?
Other stuff:
exhaust leak or tick
Anything loose in the engine bay
Have you checked your plugs?
One cylinder might not be firing as well as the others, sending unburnt fuel past your O2, and could cause your engine to run lean.
Or maybe a clogged injector?
Oil. I'm convinced that my heads were leaking oil causing predetonation.
Does you car loose a noticeable amount of oil between oil changes?
Other stuff:
exhaust leak or tick
Anything loose in the engine bay
Have you checked your plugs?
One cylinder might not be firing as well as the others, sending unburnt fuel past your O2, and could cause your engine to run lean.
Or maybe a clogged injector?
#7
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Looses lots of oil, only visible leak is the LIM
Exhaust leak maybe
Plugs are a year old, haven't looked at them recently
I'd notice if a cylinder wasn't firing
Injectors were cleaned/rebuilt last year
Exhaust leak maybe
Plugs are a year old, haven't looked at them recently
I'd notice if a cylinder wasn't firing
Injectors were cleaned/rebuilt last year
#8
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Exhaust leaks are a big suspect on the S1 due to cracks. Or the knock sensor itself rattling. Did you use any kind of goop to put it in? What makes you so sure it'* false? Octane alone cannot kill all KR. If you have an exhaust restriction, no amount of octane will save you.
#9
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I figured it was false cause it didn't change with higher octane. I guess I could be wrong. What could cause the massive KR at the top of second? I installed the knock sensor dry, except for the red threadlock that was already on it.
I'm starting to get the feeling it will completly disapear when I swap the heads, LIM, and manifolds.
I'm starting to get the feeling it will completly disapear when I swap the heads, LIM, and manifolds.
#10
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Yeah there'* really quite a few things that could cause it. Make sure your trans tube isn't rattling, tighten down your exhaust, wiggle the idlers to make sure one isn't going crazy at high rpm'*, and make sure you didn't overtighten the knock sensor when you installed it. That'll make it overly sensitive.