Ferocity02

iTrader: (59)

Ever since getting EFILive I've been trying to get rid of an area of knock. It happens at low RPM (1200-1700) and low-mid TP (20-40%) when cruising. When it happens I can't hear anything, the KR just spikes straight up to 8 deg sometimes and slowly ramps off if I stay on the throttle.

I knocked down the timing in this area about 5 deg, it's now lower than the STOCK LOW-octane table. My new low-octane table is 8 deg lower than the high. I then tried going from 87 octane to 91 and it didn't help.

My valvetrain is noisy, I can hear a tapping while cruising with the radio off. Annoying as hell, but that's what the radio is for Perhaps the knock sensors are hearing my valvetrain noise?

The next step I might try is to knock down the timing even more, maybe another 5-10 deg. And if that doens't help then something is fishy

I can post tune and logs later.

1969x11

iTrader: (38)

I'm having the same problem but I'm running the 99 pcm,i had to desensitize my knock sensors a little and it still gives me false knock from time to time. I hate to fool with them anymore because I'm at 13psi and no meth.I was told to log burst knock along with knock retard and my kr was probably burst knock. If you had somwhere to buy some race gas that would tell the tell.

MikeGyver

iTrader: (5)

Or to save money on race gas, log burst knock.

Ferocity02

iTrader: (59)

I have logged burst knock retard, but I'm laying onto the throttle slow enough for burst knock not to kick in. The knock retard PID in EFIlive does not include burst knock retard anyways.

When I'm getting knock retard there is a little bit of spark advance from the EGR spark table. But I still had this issue even without EGR.

Ferocity02

iTrader: (59)

There is no where in my area to buy race gas. If a 4 point jump in octane didn't help I'm not sure race gas would either

MikeGyver

iTrader: (5)

Do you have EGR or not? If not, you need to zero out the table.

GMCtrk

iTrader: (27)

EGR should be disabled in the tune if it's not physically there.

Ferocity02

iTrader: (59)

I currently have the EGR valve with the stock EGR spark table, and am getting knock retard.

I still got knock retard w/o the EGR valve but with the stock EGR spark table (tuner forgot to zero it). Could be wrong, but I don't think the PCM will use the EGR spark table if the EGR is not connected and is throwing EGR codes (which it was).

EGR will come off very soon after smog and before turbo.

GMCtrk

iTrader: (27)

If all the 8* KR spikes I've had in the past years of logging my truck were true knock, my motor would be in pieces by now.

MikeGyver

iTrader: (5)

I am pretty sure that if the ECM is commanding EGR, then it is using the EGR spark table. Maybe the EGR valve is stuck shut? If it is, the lack of exhaust gas in the air/fuel mix would cause detonation.