Thread: KR is winning!!!

I was having similar issues with cruise knock up to 10* when uner light load and in overdrive. Disabled EGR and it dropped to around 3-4* scanned and compared with EGR vs no EGR saw around 5* increase in timing with EGR enabled. With EGR off my mpgs got worse by about 3mpg . I looked at EGR under hood and all looks fine, car has 26K miles. I reduced timing in the cruise/knock area at 1600 - 1800 rpm by 4* and knock is gone. MPGs are back up. I'm just wondering since opening up the exhaust and having less back pressure if it affects the amount of exhaust getting through the EGR valve and into the cyclinders, so the PCM thinks it needs more timing advance than it really needs. Just guessing but it's the only theory I can come up with.

Originally Posted by Stonewall

I'm just wondering since opening up the exhaust and having less back pressure if it affects the amount of exhaust getting through the EGR valve and into the cyclinders, so the PCM thinks it needs more timing advance than it really needs. Just guessing but it's the only theory I can come up with.

To be honest, that does make some sense. There is some vacuum in the intake that sucks the exhaust through, but I wonder how much back pressure really plays in to it.

Originally Posted by TDCRacing

So you reduced the main spark tables timing? low and high octane? Were they modified to begin with? Anybody can reduce the timing or add fuel usually to make kr go away but in my opinion there is a better way of doing things. In this case it would be to find the cause of all this. I Would never reduce the timing tables to anything less than what they were stock.


And I have never heard of MPG going up with reduced timing.

With EGR off timing was reduced everywhere and mpg suffered. There is nothing stock regarding the PCM. HPtuners does not support 2006 GP. Yes reduced main high/low timing tables. I looked at the difference with egr on/off and compared timing difference as I stated in my original post. This is cruise knock not WOT knock.