Trying to defeat knock...log inside...
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Trying to defeat knock...log inside... Can somebody look at this log and give me some ideas about this knock? It is pretty consistent about 3800-4000 rpms. I don't know how high it goes, but the knock starts to settle down and the engine continues reving without more most of the time...I don't get it...
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Joined: Mar 2002
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Is it sucking oil through PCV ?
Harmonic balancer going out ?
Exhaust banging ?
02 voltages seem to be on the rich side. That combined with low timing you're getting it shouldn't be real knock unless you're sucking oil or running real rich and heads are dirty. Have you tried top-end cleaner ? I suppose you're using 93 octane.
Harmonic balancer going out ?
Exhaust banging ?
02 voltages seem to be on the rich side. That combined with low timing you're getting it shouldn't be real knock unless you're sucking oil or running real rich and heads are dirty. Have you tried top-end cleaner ? I suppose you're using 93 octane.
There is only a little bit of true WOT in that 'sheet
(cell 15/22). For the most part it looks like you're
messing with the pedal and the knock is precipitated
by that "lean hole" you are getting at tip-in (see how
the O2s "crash" to 80mV at line 600, right as you are
opening throttle to go WOT, and your first KR shows
a couple of lines before TPS=100%).
I believe there is "stuff" that can be adjusted to deal
with tip-in knock (like burst knock timing pull to just
keep from pinging / KR, I expect there is also some
tip-in enrichment param(s) though I don't know if
these are made accessible in the software; I don't
recall seeing anthing like this in the tabs but seems
there should be a "handle").
Cells 2 & 3 start out showing positive LTFTs but these
drift over the course of the log indicating the car is
learning. It may be that whatever you've been adjusting
has not fully bedded-in yet.
(cell 15/22). For the most part it looks like you're
messing with the pedal and the knock is precipitated
by that "lean hole" you are getting at tip-in (see how
the O2s "crash" to 80mV at line 600, right as you are
opening throttle to go WOT, and your first KR shows
a couple of lines before TPS=100%).
I believe there is "stuff" that can be adjusted to deal
with tip-in knock (like burst knock timing pull to just
keep from pinging / KR, I expect there is also some
tip-in enrichment param(s) though I don't know if
these are made accessible in the software; I don't
recall seeing anthing like this in the tabs but seems
there should be a "handle").
Cells 2 & 3 start out showing positive LTFTs but these
drift over the course of the log indicating the car is
learning. It may be that whatever you've been adjusting
has not fully bedded-in yet.
Thread Starter
TECH Addict
Joined: Feb 2004
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I have been considering using top-engine cleaner...it is sitting in my garage. Would it really be necessary at 34k miles? If so, I am prepared to put it in. I even have a fall-back plan. I heard if the top engine cleaner doesn't work, slowly (very slowly) put 2 gallons of water through the engine and steam-clean it.
I have a March fluid-filled balancer. I doubt that is the problem, I am sure it is better than that rusty junk I pulled off. I don't think it is my exhaust banging. I pulled it all apart yesterday checking, and it seems ok. I hear a tick from under the car, but I am thinking it is just the headers (does that sound normal?) because I used a mechanics stethoscope on all the joints in the exhaust and I didn't hear anything. And if it was an exhaust leak I wouldn't think it would be so consistent?
I always run 93 octane, and I have fairly regularly ran the add-to-gas cleaner throught the engine (yearly at least).
I also switched over to the fixed orifice style PCV, so I doubt oil is getting through. I never really had an oil consumption problem in mine anyways.
As for the programming ideas....I am going to look through HPTuners for that stuff...any ideas where to look and where to set it to?
Thanks in advance for all your ideas!
I have a March fluid-filled balancer. I doubt that is the problem, I am sure it is better than that rusty junk I pulled off. I don't think it is my exhaust banging. I pulled it all apart yesterday checking, and it seems ok. I hear a tick from under the car, but I am thinking it is just the headers (does that sound normal?) because I used a mechanics stethoscope on all the joints in the exhaust and I didn't hear anything. And if it was an exhaust leak I wouldn't think it would be so consistent?
I always run 93 octane, and I have fairly regularly ran the add-to-gas cleaner throught the engine (yearly at least).
I also switched over to the fixed orifice style PCV, so I doubt oil is getting through. I never really had an oil consumption problem in mine anyways.
As for the programming ideas....I am going to look through HPTuners for that stuff...any ideas where to look and where to set it to?
Thanks in advance for all your ideas!
