Mostly stock 3800 NA with BAD knock, help?

[tyroelite]

Hi guys, I'm new to tuning and just did a few scans with my HP Tuners but from what I can tell, I think there are some obvious issues with my current tune and I should be able to pick up some real power and gas mileage.

[Logs Attached below]

My mods are just DHP PCM (also have original PCM if necessary), FWI w K&N FIlter, flowmaster mufflers. Its a base GP 3800 (2005 model) so no boost or anything crazy.

Log 3 is a WOT run onto a highway... thats what I'm reffering to mostly below

I go WOT at frame 482 and I get some crazy knock (not sure if its phantom knock or real knock... its different than I've seen in other logs)

Also, I have timing advance up over 40 and knock retard up over 8 at different times. The csv doesn't show the INJ Duty % but in that period of WOT, it gets up to a max of 125! It varries some but hovers near 100% sometimes over sometimes under. Something doesnt seem right... can you offer any help?

Does this look like real knock or is real knock more of a steady increase to a peak and then drop off. What I'm seeing is more of a step pattern, 0->5.5->5->7->6->8->0
I get the knock under WOT but I also did a scan with cruise control on 60 on the highway and it was knocking pretty steadily a similar pattern peaking at about 4 or 5.

So any ideas?


BTW, Log2 is a highway run for a good portion at about 60MPH and also has some WOT onto the highway and Log1 is some random driving around as the car was warming up.

[tyroelite]

bump

I also switched back to the stock PCM and I was still getting knock. It wasn't QUITE as bad but still more that I'd expect with an intake and mufflers. It peaked at 6 degrees and under any full throttle, it was constant. At least on the highway I'm not getting knock anymore.

So can anyone offer any help on this?

[Russ K]

You need to post your stock & modified tune that are from your scan logs. On the V6 cars, I zero the AFR spark correction table. Then I multiply the High Load knock retard decay table by 4 & multiply the Base Retard table by .75.
This will help with the false knock.

Russ Kemp

[Onyx Dragon]

I had an 01 GP GT with an N/A 3800 engine. It had a LOT of KR stock as well. I'm not sure why GM does that to those cars.