Also, check the knock sensor to make sure it's tight. If it's loose, it will rattle, which will cause all kinds of phantom knock.....just something else to check on.

 

Raptord, did you test your knock sensor before you replaced it? I’m wondering if there are any tests I can do to let me know that the sensor is bad. It is a lot of money and time to replace that thing. I’m not sure if we have the same symptoms either. I only register knock when step on the gas paddle hard (floor it). Knock spikes almost at the same time I go from closed loop to open loop. You said you got 36 counts under normal cruising without flooring it?

I have some logs I can post later on with perfect runs and timing seems to be pretty smooth no spikes or jumps. This car is tuned by a very reputable tuner. I don’t want to post his name since I have his maps up. But the tune shouldn’t be a problem because the car was running fine for a long time.

I’ll check the knock sensor tightness, is there any easy way to get to that thing?

Thanks again guys for the inputs.

 

Sounds like something is loose, rattling

 

It's a real ***** to get to the sensor, it's all the way behind the block. I wanted to change it myself but there was no way I could do it. The easiest way is from under the car. We didn't test the sensor before replacing it. The knock sensor itself was about 100$ at the dealer, and it took about an hour to replace it. At 75$ an hour for labor, it was about 200$ total for the new sensor.

Here's a sample from one of my logs:

 

Thanks for the logs. Looks identical to mine. I will definitely do some continuity checks on the knock sensor circuit tonight after doing a boost leak test. One more question, did the dealer try to diagnose? or did you just ask them to replace the sensor?
I wonder how good they are at diagnosing evos.

 

I didn't bother with the dealer; since Evo VIII's and IX's weren't sold here in Canada, dealers very rarely see one let alone work on one. I went straight to a performance shop. My tuner figured that the sensor was bad judging from the logs I sent him, so I ordered the sensor from the dealer and had it installed at a performance shop.

 

Ok, I ripped the intake off and there was a lot of oil or oil and coolant in the intake pipe to the turbo. There is a lot of shaft play in the turbine. Can this be the cause of my problem???
I must have had the intake off like two months ago and I checked it then and turbo was fine. Let me know what you think

 

Hm, maybe the shaft play has a certain sound that is being picked up by the knock sensor? You'll definitely want to have the turbo fixed though, regardless of whether it's causing the knock or not.

 

I have a big boost leak and 5k rpms it knocked 4 times, and that was it, so even if you have a boost leak I think it's something else

 

If a lot of oil makes it's way into the air/fuel mixure, it will lower detonation threshold and depending on how much is present, it can be a real problem. I doubt this is your issue though, because it would have to be a good amount to cause the knock you're seeing and by this i mean you'd probably be able to see it as smoke after it's burned in the combustion process. Is your car smoking white smoke?

If you're still using the stock PCV system and are not venting it to atmosphere or catch can, oil in the intake is completely normal. This is crankcase venilation that is routed back into the intake for emissions and can cause a mess in the intake, turbo, intercooler and piping.

What kind of shaft play are we talking about here? Lateral play? Because the turbo is a journal bearing turbo, there will be a certain amount of shaft play....is there scaring on the inner diameter of the compressor housing inlet, like the compressor wheel blades are touching the housing?

 

One more question. When you're registering the knock, do you hear the knock? It will sound like marbles in a tin can, at it's extreme. Can sound more like popcorn popping too, depending on how bad the pre-ignition or detonation is. Bad knock should be able to be heard from the cabin with relative ease, with a well trained ear. I can hear even the slightest knock very well....but you have to know what to listen for.

If you really wanna get technical and don't mind a project, get yourself a set of det cans(google det cans) or make your own.....to see if this is actual knock or false from a noise elsewhere.

 

I do hear the knock and yes it does sound like marbles. There was oil in the intake pipe too so oil/coolant was making it's way into the combustion chamber. I don't think there should be any oil/coolant leaving the turbo, correct?
As far as the shaft play goes, it's lateral (NOT along the axis of the turbine shaft). There are some markings on the compressor housing inlet. Last time I checked my turbo, this didn't exist.
I just ripped the turbo out and will take it apart tomorrow and see how the bearings are. Might have to rebuild. I will also drain the oil tomorrow to see if any coolant made it into the oil pan.
I hope the turbo just let go and it wasn't something floating around in my engine braking stuff. Kind of makes me worried that it happened after an oil change.

 

I think my car doin same thing
did u have a WOT logged run? I noticed with the 30 plus counts of knock timing was in the 20's and should of been in lower single digits

 

I have a 2005 evo 8.5 turbo for sale. It's got zero play and is in great shape. Because it's a 2005 turbo, it's got a 10.5 hotside. I made 380whp with this turbo....let me know, i'll sell it to you on the cheap.

Are you sure there is coolant in the turbo inlet?? Oil is normal if the turbo is shot, but coolant from the turbo is rare. It's possible the CHRA got really damaged and coolant is leaking from it and making it's way into the compressor housing and possibly the turbine housing as well.

 

That is a WOT run. You can see the throttle position is 100% most of the run. Timing is actually -10.

I’m going to try to open it up and see if rebuilding is an option, I’ll PM you if I will need your old turbo.

I actually think it might have been oil and coolant since it wasn’t as thick as oil usually is. It’s kind of hard to tell. But I’m sure I’ll know for sure when I open it. Look for pics soon.