Have an 07 Sierra that was just rebuilt that I'm trying to get dialed it. Heads have been ported, stage 2 truck cam, cold air and long tubes. Considerable milling done on the head and block during rebuild, running 7.285 pushrods.
So since i've had it back together, I've been battling a random knock issue that i can't seem to figure out. It seems completely random and it usually doesn't seem like it's actually knocking, but this morning it was definitely rough. The last week or so I've been shifting over to E85 to see if the higher octane would help cut the knock down. I got the maf looking pretty good and then switched over to VE, got that looking fairly good and then last night re enabled the maf and set the dynamic airflow stuff back to stock, so the truck would run off both tables as it does stock.
I had desensitized the knock sensors at one time trying to eliminate false knock, and went ahead and set those values back to stock also. Knock is way worse this morning than it has been, even though my fueling should look pretty decent. It's definitely running rich this morning, but I kind of expected it to be off some as it's cold this morning for the first time all year and Ive been tuning in warmer weather. The knocks seem to be at part throttle or tip in, but it doesn't seem consistent. The knock is usually less than 1* of retard at random times. I really am at a loss as to what my fix for this is, any advice would be great.
These logs are me VE tuning and then the 2 from this morning are 1 while it was still warming up, and the 2nd one my laptop died on the way to work. So not great data but you can get the gist of what it's doing and how it's running. Felt like it was running great yesterday after I had the VE table looking good, this morning felt sluggish and just all around not great with the maf reenabled.
My main concern is getting the knock issue figured out, another thing I really dont know how to fix is the super rich idle, especially on the low rpm/kpa sections on the VE table. Plus it always seems to idle rich....would I need to add more airflow to the idle base airflow table? Also stumped on that.
Yesterday while logging VE, even though I wasn't lean, the truck did make a couple hard misses....i would've expected it to be bad knock but it didn't register anything on the scanner. Other than that, the truck ran better on VE only than it has since I've got it put back together. The misses were at part throttle....maybe tip in or a little after.
Any advice or tips is greatly appreciated! Thanks,
10-18.hpl
10-18 2.hpl
10-18 3.hpl
10-18 4.hpl
10-19.hpl
10-19 2.hpl
Updated knock sensors.hpt --most recent, reenabled MAF and set knock sensors to stock
VE TUNING.hpt-- previous tune, set for VE logging