Phantom Knock Issues

[Nonrml4]

Buddy just got the motor back together and is trying to sort issues out, we are both stumped.. The car was stock motored w/ 16g with all supporting mods running 26psi on a 50/50 e85/94 octane mix. Started pushing coolant on the stock head gasket, motor was disassembled, now trying to tune the new setup some issues have arisen, the motor now has cams and a built bottom end w/ 16g turbo. Here are some pulls, there doesn't seem to be any rhyme or reason. Any help could be great. It has us both stumped.

 

[Nonrml4]

Here are the logs. I also have the excel file if I could send it to anyone to take a look see.

 

[TxR6guy]

When is the Knock lite comming on? in the top of the rpms? also what is your base and WOT timing set at?

What im saying is my buddy is running 80/20 mix on E85 and if we put the WOT timing at 19.5 he's getting knock still...

may try lowering your timing and go from there. his base timing is 5dg and wot is 18dg w/ 0 knock.

I dont know if this is the cure but something to look into.

 

[turboglenn]

My AC compressor had been driving my J&S knock sensor crazy lately. When the AC is off it is less frequent, but after pulling the belt today it ALL went away. You wouldn't believe how much noise it was making in the block, and i even had the J&S's sensitivity turned all the way down to "3" (from 0-10)

Your very fist log pic (top) when the knock is super bad looks like my logs when the AC compressor is making noise when driving slow in a parking lot (especially how TPS and RPM are exactly like what mine is doing)... Pull that belt to at least eliminate that possible cause, if it don't change, put it back on.

Also, cams can make a motor a little more noisy/knock happy. Mine definitely made an increase in motor noise, and i'm not sure if it's more about the extra travel and ramp rate on stock springs, or the fact that i had to shim the lifters because they were regrind cams and maybe that is making noise *shrugs*.. i'm stumpoed on this one but haven't focused too much on it really

TxR6guy...his timing is on the far left column (took me a minute to find it too)

 

[Nonrml4]

When is the Knock lite comming on? in the top of the rpms? also what is your base and WOT timing set at?

What im saying is my buddy is running 80/20 mix on E85 and if we put the WOT timing at 19.5 he's getting knock still...

may try lowering your timing and go from there. his base timing is 5dg and wot is 18dg w/ 0 knock.

I dont know if this is the cure but something to look into.

The logger is showing knock during light acceleration and even during free rev.. we aren't sure what the best course of action is. Timing is in the left column.


I will send my buddy a link to this thread and I am sure he will chime in.

My AC compressor had been driving my J&S knock sensor crazy lately. When the AC is off it is less frequent, but after pulling the belt today it ALL went away. You wouldn't believe how much noise it was making in the block, and i even had the J&S's sensitivity turned all the way down to "3" (from 0-10)

Your very fist log pic (top) when the knock is super bad looks like my logs when the AC compressor is making noise when driving slow in a parking lot (especially how TPS and RPM are exactly like what mine is doing)... Pull that belt to at least eliminate that possible cause, if it don't change, put it back on.

Also, cams can make a motor a little more noisy/knock happy. Mine definitely made an increase in motor noise, and i'm not sure if it's more about the extra travel and ramp rate on stock springs, or the fact that i had to shim the lifters because they were regrind cams and maybe that is making noise *shrugs*.. i'm stumpoed on this one but haven't focused too much on it really

TxR6guy...his timing is on the far left column (took me a minute to find it too)

He tried two different knock sensors and we are sure that the knock sensor is functioning properly.

Exactly.. which is why it is so hard to understand. I will pass that on to him.

I understand that. He also had an issue of slipping a tooth on the timing belt and it taking out the exhaust valves. He just replaced the lifters from that escapade, and thinks that some noise could be coming from there. But at some points it seems to settle down. Thanks for the responses guys! keep them coming

 

[turboglenn]

Man the light accel and free rev knocking were the things that were driving me nuts and i couldn't figure out, iut ALL went away when i pulled the AC belt. It's worth a try, i mean spend 15 minutes to elimintae it or spend hours and days chasing around it if that is the noise and you don't pull the belt to be sure.

I was sure my motor was on the virge of coming apart honestly due to the amount of knock being picked up and how frequent it was happening in very low RPM low load ranges and especially easy to duplicate on free revving. I'm glad i found my issue before tearing into lifters, checkcing rod bearings and playing with oil pressure mods etc..

 

[StockBiotchs]

the car is a A/C delete car.... there isn't even a compressor in the car.

base timing 5*

 

[bastarddsm]

I'm baattleing PK to...i bought aa new knock sensor from carquest it helped some. better yet, #### phantom knock and the horse it rode in on!

 

[turboglenn]

the car is a A/C delete car.... there isn't even a compressor in the car.

base timing 5*

Well, that elimntaes teh need to check the A/C then doens't it Man these cars are such a PITA, but i still love them. Good luck hunting it down, if i think of anythign else i'll post it in case it's something you guys haven't thought of. I was really hoping some one else would find such an easy fix as i did, even though i put my belt back on last night it helps for me to know that there is a way to get rid of my PK issues. Good luck !!

 

[StockBiotchs]

the most confusing part is the light load knock....

Looks like it will be coming back out of the car, there has to be something...

would a broken ring act like this?? when I took out the exhaust valves, it wasn't pretty, I also lost 4 guides..... the head was sent out and re-coned

Thanks for all your input

I am going to check compression .

 

[turboglenn]

What type of pistons did you use in the motor? I've had some issues with JE pistons in the past making the knock sensor go off like crazy. They have a different silicone content in their alloy which makes them expand slowly and they will slap like crazy untill the motor has really warmed up and ran hard for a while.

 

[StockBiotchs]

Ross pistons,......

I am an idiot, I had mounted the knock sensor too high on the block. I put it where it should go and things seem fine..... Thanks for your help

ran 20 psi on it tonight and registered a 5 knock count

Thank you !!

now more boost and bigger injectors

 

[turboglenn]

Glad you got it sorted out...PK is one of the biggest reasons i hate dealing with a stock ECU on a mitsubishi. YOu can fart too loud and transfer enough vibration to set the damn DSM Knock Sensor off .

 

[2point3Tsi]

So if farting too loud causes PK I want your aftermarket knock sensor now!

Just curious, what brand and how do you like it? Also how do you 'mount' it? Tapping? and do you just replace the current ecu signal with this one?