KR Issue and Tuning Help

[Turbovan]

I've been getting my truck ready to get properly tuned but have noticed a bit of an issue when taking it for a spin. It seems to be reading some KR at weird times, and I dont think I have the timing set very high. The combo is a 4.8 with forged pistons, deka 80s, EFI source 2 bar MAP, SS2 camshaft, borg s475 on the side running 94 octane fuel. 4l80e trans with FTI 3200 converter. Plugs gapped to 25 thou, NGK BKR7E plugs. Its running open loop SD, and the O2s arent accurate.

I took it for a little spin for the first time and noticed the KR readings. The wideband is hooked up inside the truck, but not reading in HP tuners unfortunately, but its a tad rich still (Low 13s). It seems to read KR when I was slowing down and the trans downshifted putting it under load.

Here is the log (really long I know) and the tune, im still figuring things out on this so its probably way off but any insight is appreciated.

[5FDP]

Check for codes while it's running, see if you have an pending or current knock sensor codes. Those can cause knock spikes in the logs.

Also make sure nothing is rubbing on anything.

[Turbovan]

It has a fender dump out the side that vibrates on the fender a bit, which I suppose could be an issue. I'll take a look for other things rubbing, how sensitive are they really? The only codes I have are for the MAF and heater codes because I removed AC and the heater box is unplugged, otherwise nothing.

[blindsquirrel]

You can tap on various things with a small hammer while monitoring the scanner, you know. Learn for yourself how different parts on your vehicle respond to different types of tapping.

[corvet786c]

You can tap on various things with a small hammer while monitoring the scanner, you know. Learn for yourself how different parts on your vehicle respond to different types of tapping.

I also am trying to find some KR issue, mine ranges from 1 to 3 degrees. This sound like a good start to use a hammer while scanning. I have a quickjack, I can just raise the vehicle while its scanning and idling. I also noticed that WOT about 4000 rpms I get it and making turns.

[Turbovan]

I took a look at everything and fixed a few things that are rattling, I even took a lot of timing out everywhere and it?s exactly the same. Reads knock on deaceleration and other odd times, nothing under load though.

Do the knock sensors go bad typically?

[danmw2003]

They are supposedly, one time use. Not sure how true that is, but if they were removed from the block, might try getting new ones. I've never removed and reinstalled them. Just a thought

[Turbovan]

They are supposedly, one time use. Not sure how true that is, but if they were removed from the block, might try getting new ones. I've never removed and reinstalled them. Just a thought

Hmm I did have them out when I did the motor and put them back in, they were torqued properly too. I might have to test them.

[Turbovan]

I did some more testing. I did 2 runs, each time I pulled about 20 percent timing out of it and the KR in the scanner didn?t really change. I?m new to this but it?s still very strange to me that the retard wouldn?t get lower or be eliminated. No knock detected during acceleration where there is more load.

[kevin87turbot]

I did some more testing. I did 2 runs, each time I pulled about 20 percent timing out of it and the KR in the scanner didn?t really change. I?m new to this but it?s still very strange to me that the retard wouldn?t get lower or be eliminated. No knock detected during acceleration where there is more load.

The engine isn't going to detonate under deceleration. You can rest assured that it's false spark knock.