ok now i think something is wrong with my car. ive turned the boost down to 16 psi and its still there, turned it back up to 20psi still knockin, my dp was rubbing so i took it off and dented it where it rubbed, still didnt fix it. i had knock before my cams were installed and after. been through 3 different e-flashes and still knocking. changed my plugs, still knocking.

the interesting thing is i went out tonight and drove my car up to high rpm's without any load and still got knock. thats right no wot, no boost, still knock.

i also did a normal 3rd gear pull at 20 psi falling to 19.7 at redline and yep you guessed it the knock is there. here are my logs.
let me know what you think i should do next cause im clueless?

also mod list is 272 cams, ebay o2 housing, 3"tbe no cat, apexi intake, walbro fp, mbc, 93 oct and a jestr eflash. car only ran a 12.3@110mph with a 1.8 60ft. ive been told it should be faster. can anyone help me out?

 

Are you using a nice flat road to do the pulls on?

 

Seems like the harmonic vibrations you receive at those RPM's are rattling on something, causing you to get phantom knock..

 

yeah they are pretty smooth. its in every log i do too.

 

well the other day i had counts as high as 14 so i dont think thats phantom knock but then again im no expert so....

 

seems kinda lean... 11.9-12.2 higher up.... i would shoot for 11.4 - 11.7

give that a shot and see what happens

 

ok i'll try that.. one question tho cause ive never tinkered with my ecu flash. do i take the load calc from my evo scan log and the rpm and modify that cell in ecu flash or is the load calc from evo scan different from the load in ecu flash?

 

Yep you look a bit lean to me as well. The load calculation is pretty close. You can figure out exactly where it is by looking at the timing in that map, locate the point, and adjust the fuel table to suit it.

 

its a little more complex than just changing numbers..... even though thats what your doing.... you start from the max load at highest rpm and work yourself back wards...


ex. you max rpm and max load is probably something like 11.8/11.9

i would drop all those load numbers from 4500+ and 160 load down .3 in a roundish fashion...

not a big drop off..

im not a pro when it comes to tuning, im having jestr doing mine, but i understand the concept and have the fuel part down.... im working on fully understanding timing... but from your logs it looks good

cheers!

 

actually before i change anything take a look at this log from a few days ago. a/f was in the low 11's and i hit knock in the teens. this was at 21-22psi. thats why i think its something else besides the tune. https://www.evolutionm.net/forums/sh...d.php?t=243216

 

Try a known good knock sensor.
The one you might have in the car is on it's way out.
.

 

has anyone ever found it to be a bad knock sensor? my car only has 13k miles on it and its an 05 so im doubting thats the problem but i will see what i can do just to rule it out. anything helps so thanks for the idea.

i was gonna try a boost leak test to see if i had a leak and the turbo was working extra hard to make up for it and generating heat but since i did that log with no load and still got knock im pretty sure thats not it anymore.

im gonna do a comp. test next week but other than poor performance i dont know if bad compression will cause knock will it?
any other ideas?

 

Try to change boost like -3 to -4 Psi. If knock count still the same, it's noise.

If the knock is going lower it's probably real knock.

 

I don't necessarily agree with the above statement. Vibrational harmonics may not cause the same knock counts each time. Heat, air density, many other factors come into play.

Throughout my ordeal with trying to track down knock as exhibited with EvoScan I’ve found out that many – many – things can cause phantom knock.

One of the main culprits of phantom knock is the DP and it’s clearance in relation to the crossmember.

Something as simple as a loose bolt in the engine bay can sometimes be picked up as knock. Something rattling in the head can also be a major factor.

I did some major testing when tracking down my knock issues.

1) I loaded my completely stock map and did many pulls. I saw counts as high as 20!
2) I then did many pulls with my boost turned all the way down. This still showed signs of knock.
3) I also dumped in some race gas to see if knock was still present and found that in some cases there was knock.

If you’ve done all of the above it’s safe to say that you have some kind of phantom knock occurring.

Some other factors to consider:

Do you have aftermarket motor mounts? This can cause a lot more vibration.

When you do your pulls are you doing it in the same place? Is the road bumpy? Potholes etc? Believe it or not – this can cause knock sums.

Till this day I sill get knock counts. I’ve learned to live with them until I can thoroughly go over my engine compartment and see if there are any issues there.

Hope this helps.