Originally Posted by MalibuJack

If its registering knock in that RPM range, it certainly is possible since it would pull timing..

Instead of playing with the fuel, did you try removing timing to reduce the knock? If that had no effect then its likely some sort of resonance from the transmission or valvetrain.

Are they verifying that its knock using cans?

The knock threshold can be adjusted to be more or less sensitive in the low, mid, and high rpm Ranges.. I have mine configured to be more sensitive and I don't get much "Racket"

Its certainly possible to have a defective O2 sensor, but the O2 sensor is only used to control closed loop fueling, if you find you cannot make adequate adjustment for it, you may have to play with the STOCK INJECTOR SIZE parameter in OLF.. If you change ANYTHING remember to RETUNE THE CAR..

Do you find your fuel trims are wacky with the 550/740 setting? (did you already have a reflash?)

Its possible to replace the O2 sensor, but the knock sensor is basically a piezo microphone, It either will work, or it won't, its discrimination is at the control of the ECU or UTEC..

In my experience that studder at 5k was due to my ignition system not able to provide a good enough spark..

Have you tried LOWERING YOUR BOOST in the map? Telling me that it doesnt happen in stock mode, without testing lowering the boost in a tuned map isn't going to tell us alot.

Al has pointed out a few times that around 5k seems to be a "Resonance or Harmonic" area that alot of engines seem to produce noise that may be seen as detonation, or it may really be detonation and timing would need to be removed so there is less advance in that range..

My experience even with my NGK colder plugs (BPR7ES) plugs, that gapping them at greater than .030 seemed to result in misfiring or spark quench when I gapped at .025 or .026 I noticed it went away.

Also, check your coil packs.. if you have access to borrowing someone elses packs and wires, swap them on and test again.. you may have defective coils..

I doubt the UTEC is defective, though anything is possible, but more often than not, its just something overlooked, even check for boost leaks.

Check your fuel pressure too.. Though your not seeing the car run lean in any sense of the word, its worth checking.

Also, you can get a misfire if the car is running rich too, combine a rich mixture with alot of timing advance and a weak spark and it can result in it..

What are your EGT's when running these tests?

Originally Posted by dopeman_420

put your stock plugs back in if there still good or go mitsu dealer and get a new set.i had a similar issue when i went to brainstorm performance to do a power run on there dyno. a day before i went i switced to the brp7es plugs.so we ran my car but probs arose it didnt even dawn on me the ngk were the issue until i told them i was running a colder plug.the tech said those are good plugs he ran them in his dsm but the evo runs high boost[as we all know] and those plugs cant hang with that much boost.so he asked me were the original plugs were i said i threw them away he said[mistake] as i only had 2000 miles on them and had to have one of there staff go get me a new set at 100 and some change from mitsu dealer and that cured my problem.

Originally Posted by MalibuJack

Yeah I would at least try different plugs, colder plugs CAN lead to a misfire, but generally under higher boost you WOULD use colder plugs since the tips don't retain as much heat and aren't a "hot spot" that can start a spontaneous combustion event.

A misfire is different than detonation, a bad misfire can result in either somewhat low, or somewhat high EGT's (Depending on if the remaining mixture combusts in the exhaust manifold)

The gap should still be around .025 or .026, if you gap at .030 or .035 and have a weak spark for any reason, it will result in a misfire too so check your plug gap.

The NGK's are not bad plugs, but don't have much of a lifespan (you should change them every 5000 miles or every oil change cuz they work good, but their cheap)

Originally Posted by MalibuJack

Yeah it could be a weak spark due to how the coils are fired, or whatnot..

Did you create a map with fuel map only, removed all timing (Set to ECU) to see if it still does it?

ANyway I guess its not important since you shipped it to them to check out.

Originally Posted by MalibuJack

DOH.. I can feel that transition from closed loop to open loop on some occasions.. I thought I had posted something about that at one point but I looked in this thread and made no mention of it, and if I posted it in another thread, it was likely a response to part throttle stumbling when driving on the parkway (Raising the OLF transition point)

Oh well, at least its fixed.. What confused me was the testing method.. you never said that this didn't happen when driving, only when you free revved the motor..

Originally Posted by MalibuJack

DOH.. I can feel that transition from closed loop to open loop on some occasions.. I thought I had posted something about that at one point but I looked in this thread and made no mention of it, and if I posted it in another thread, it was likely a response to part throttle stumbling when driving on the parkway (Raising the OLF transition point)

Oh well, at least its fixed.. What confused me was the testing method.. you never said that this didn't happen when driving, only when you free revved the motor..

Originally Posted by Imprezd

Jack, if you can feel the transition it's because you still need to smooth your transition point. Most of the time you can see it immediately, you’ll have a large IDC jump + or -. It's pretty simple to smooth it out.

Thanks,
Jermaine~

Originally Posted by TampaTurbo

How do you smooth out the IDC? I think I have noticed that before in many logs.

Jermaine, If you come back to this thread, would you say that Mark at TT can call you while he is tuning the car for me if there are any probs. He will be putting on their turbo kit for me in a few weeks and I want a very smooth powerband when it hits OLF. I cant imagine how harsh the feel would be with a larger turbo and everything kicks in at different points.

Originally Posted by Imprezd

Basically to smooth the idc's you need to add or subtract fuel. Mark should be able to sort your car out. The crossover to OLF at the RPM threshold point only happens if your are going above 5k but you are less than your tps threshold point.

Thanks,
Jermaine