Let the modding begin! (Dwight)
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Joined: Aug 2010
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This is where a base dyno run would possibly have helped. How many miles are on the engine? Raising the compression on a higher mileage bottom end can play heck if the rings were weak to start.
You mention that you had oil in the intake, but nothing in the catch can. This makes it sound like oil is going into the TB via the breather hose, not the PCV and if that is the case it would have to be blow by.
You mention that you had oil in the intake, but nothing in the catch can. This makes it sound like oil is going into the TB via the breather hose, not the PCV and if that is the case it would have to be blow by.
This is where a base dyno run would possibly have helped. How many miles are on the engine? Raising the compression on a higher mileage bottom end can play heck if the rings were weak to start.
You mention that you had oil in the intake, but nothing in the catch can. This makes it sound like oil is going into the TB via the breather hose, not the PCV and if that is the case it would have to be blow by.
You mention that you had oil in the intake, but nothing in the catch can. This makes it sound like oil is going into the TB via the breather hose, not the PCV and if that is the case it would have to be blow by.
It's possible the rings couldn't handle the bump in compression.
If I can budget the cash I may have them rip this motor out and rebuild the bottom end or build a 6L.
I might have a stock motor a friend will loan me to use in the mean time.
Here is a very basic chart to compare plugs to. This will give u a very general/overal idea of whats going on in the compustion chamber. The pics will never match the plugs exactly so you have to use this as a guide loosely as a base. There is also a mixture ring at the very base of the insulator but that is tough to see and mainly for WOT mixture.
Here is a very basic chart to compare plugs to. This will give u a very general/overal idea of whats going on in the compustion chamber. The pics will never match the plugs exactly so you have to use this as a guide loosely as a base. There is also a mixture ring at the very base of the insulator but that is tough to see and mainly for WOT mixture.
I'm just gonna put some miles on her and see what the plugs say later.
Last edited by 98PurpleT/A; Sep 1, 2010 at 11:13 AM.
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Why dont you a cylinder leak down and solve the problem with the ring BS in a hour or so instead of playing the guessing game with who reads plugs what way. Just my 2 cents. Could be a weak valve spring causing float at 5000rpm just a thought.
1. Its false knock, the plugs don't look that bad especially if these are the plugs that were installed on initial start-up? Have you been driving around on them? If so, then I think they look fine. I don't think they look oiled at all, I can't really see any specs, They should look a little lean if you have been driving it around on the street. The pcm is running it at stoic in closed loop p/t. If anything they look a little hot to me, but its a tr5, again reading them after driving it means nothing regarding pulling timing over 5000 rpm @ wot.
You need a clean read on the plugs at WOT to see if its really detonating. This means new plugs, make a rip, shut it off immediately and coast to a stop, check plugs. However, In my experience there ain't no way that car would leave Dan's shop pulling 8* of timing from real knock.
2. Valvetrain noise. Have you thought about running a stock rocker arm on the engine and logging it?
Did you re-use the lifters?
Did you check pr length, swipe?
Is it possible that there is some valve float?
Just trying to help you rule out rule out everything.
A million posts ago someone said the problem was the logs are showing knock above 5000 rpm. After looking at the pics of the plugs this makes me think 2 things.
1. Its false knock, the plugs don't look that bad especially if these are the plugs that were installed on initial start-up? Have you been driving around on them? If so, then I think they look fine. I don't think they look oiled at all, I can't really see any specs, They should look a little lean if you have been driving it around on the street. The pcm is running it at stoic in closed loop p/t. If anything they look a little hot to me, but its a tr5, again reading them after driving it means nothing regarding pulling timing over 5000 rpm @ wot.
You need a clean read on the plugs at WOT to see if its really detonating. This means new plugs, make a rip, shut it off immediately and coast to a stop, check plugs. However, In my experience there ain't no way that car would leave Dan's shop pulling 8* of timing from real knock.
2. Valvetrain noise. Have you thought about running a stock rocker arm on the engine and logging it?
Did you re-use the lifters?
Did you check pr length, swipe?
Is it possible that there is some valve float?
Just trying to help you rule out rule out everything.
1. Its false knock, the plugs don't look that bad especially if these are the plugs that were installed on initial start-up? Have you been driving around on them? If so, then I think they look fine. I don't think they look oiled at all, I can't really see any specs, They should look a little lean if you have been driving it around on the street. The pcm is running it at stoic in closed loop p/t. If anything they look a little hot to me, but its a tr5, again reading them after driving it means nothing regarding pulling timing over 5000 rpm @ wot.
You need a clean read on the plugs at WOT to see if its really detonating. This means new plugs, make a rip, shut it off immediately and coast to a stop, check plugs. However, In my experience there ain't no way that car would leave Dan's shop pulling 8* of timing from real knock.
2. Valvetrain noise. Have you thought about running a stock rocker arm on the engine and logging it?
Did you re-use the lifters?
Did you check pr length, swipe?
Is it possible that there is some valve float?
Just trying to help you rule out rule out everything.
It is so random. I drive around with my Tech2 on my lap and there is no set RPM or engine load that causes the knock sensor to go off.
It's not a matter of not really being able to find the problem it's haveing the time to do the proper checks.
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Joined: Jul 2009
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From: pembroke pines florida
d did u replace the knock sensor harness to there was a bulitan to replace both knock sensors and harness?and since u have a tech 2 what is the fuel trim reading at idle u could have injector o ring leak ,small but under excell excessive vacumm.remove oil cap while running see if shes puffing out the oil fill good indication of blow by,
d did u replace the knock sensor harness to there was a bulitan to replace both knock sensors and harness?and since u have a tech 2 what is the fuel trim reading at idle u could have injector o ring leak ,small but under excell excessive vacumm.remove oil cap while running see if shes puffing out the oil fill good indication of blow by,
