Ive been logging up to 7-8 counts of knock at low rpms from say 1000-2500 rpm. Sometimes i'll just be at a high idle for a few seconds and i get 5 counts. Most of the knock that I'm getting are also at low loads anywhere from 50-160. And it's always at very low throttle...say about 20-35 percent. I understand that this is all occuring on closed loop and i really have no control over it. Is this something i should worry about. It's driving me crazy. All other areas of my map are fine at WOT. 1 count at most in some areas but mostly knock free. Should I tune that part of the map where this is occuring even if its on closed loop?

Thanks in advance!!

 

problem has been resolved.

 

good to know what the problem was?

i had this start up randomly a while ago.. never found out what it was?

 

I've also seen this on a completely stock car running stock tune (52680018). Could you share what the problem was? I assumed it was normal.

 

Well....you might laugh cause it doesn't make any sense...lol...well maybe a little

After logging numerous of times. I constantly saw knock at the same load (50-60) and same rpm (1000-2000), at 20-30 % throttle. Now supposedly the car is on closed loop at this point. But after reviewing log after log, and looking at the timing adavnce numbers i quickly realized that they "sorta" coincided with my high oct timing map. So being where the knock was ( a part of the map with no performance value) I decided that it couldn't hurt to retard that portion of the map just to see what happens. Low and behold...the knock slowly went away completely. Now the reason I say slowly is because it took a few tries. My theory is that when the car is on closed loop it still has to get its timing values from somewhere right? It's not getting them from the low octane map, and from what I see not exactly from the high. It seems that maybe on closed loop it may taking an average from the two. So when I retarded the numbers enough on my high octane map ( which wasnt more than a few degrees) I guess it brought the average down to a level where the car ceased to knock at those loads and rpms.

Now i realize at those low loads and rpm's that knock wasnt doing much damage...but still annoyed the **** out of me. I also considered it maybe was phantom knock. But phantom knock wouldn't happen consistenly at the same load and rpm. It would be here and there, but not 5,7,9 counts all the time in the same place. So after now what must be 180 miles of testing and logging, the knock is totally gone. I will be also loading up my old map versus the new one to see if the knock does indeed come back. I'll let you know what happens. i invite you to try the same thing to see what results you also get....just to see if its just me being crazy....lol



What do you think?

 

That actually makes perfect sense. Closed loop only refers to the fuel I believe. As far as I know, the timing still should come from the high octane timing map completely unless you get very bad consistent knock. I see the same knock at 60-80 load, 1000-2000 rpm, part throttle while leaving from a complete stop. I tried reducing timing a couple degrees and smoothing it out, but it didn't help, so I assume it was phantom knock. Please post up your map so others can try it out, thanks!

 

This may sound silly but I dont know how to post up my maps......wanna tell me how?

 

Bring them up on your screen, press the print screen button on your keyboard. Its in the upper most right corner next to the F12 button. After that open up paint from your start menu or click run from the start menu and type in mspaint then press enter.

The program will start. click the edit menu and then click paste. You should have a screen shot of your map. Save it as a .png or .jpeg

Then post up the file here as an attachment. Simple as that. Id be curious on the differnces in your maps as well.

-Ethan

 

I get it all the time, I think the sensor threshold is set too low and picks up TOB noise. Also if you have a stiff suspension or a stiff motor mount it makes it worse.

 

I started noticing this exact same scenario when I started tuning my timings yesterday. Previous to that, I was never really starting my logging until I was rolling already.

I came to post the problem and found this thread.

I am trying out retarding the timings in those load areas on the high octane map now to see if "fixes" my knock. I've seen upwards of 20 counts at the extreme from a stop when I stab the throttle.

If you would share your numbers in that area, that would be helpful.