I added a Greddy catch can, 3 treatments of seafoam, new fuel filter, new spark plugs and had the stock maf replaced under warranty and still have 2-10 degrees of kr with most pinging at part throttle. Some pinging at wot, varies a lot. Gets tons worse with predator tune. Without tune or with tune my Lt's are a positive 4-8 and go to 2.34 at wot with only 17 degrees of timing because of all the damm kr. I'm gonna try using my maft again since I haven't in months.

 

what all have you done to your motor? need more info.

 

throw 20% toluene in there and see whats up

maybe its your starvin marvin gas?

 

It would be very good to get a logger on there and
see if it's single-cylinder or all cylinders (look at the
misfire active and history). Single cylinder lean (like
from crudded injector, or bad intake O-ring) would
be very visible there.

 

doesnt that predator thing log? i like efilive 6.3.3 myself

 

Predator only displays a limited set of params,
real-time, and misfire count isn't among them.

I like EFILive too (bought it, but haven't gone
and updated since 6.2.x). Maybe there's somebody
running around his locale who has that or 'Tap
and could help him out.

 

Opps my car is a 02 Z28, m6 with just a lid and predator as hp mods. The car has almost 17k miles and started this pinging, kr thing around 5K miles. I have a maft that I hooked up today and set the base at 10% rich and that got my lt's to a negative 2-3 and 0 at wot but my timing sucks at 15-17 degree's at wot and I still get some kr around 4 degree's. I don't even wanna think what the price of 100 octane is now since I'm paying 2.40 for 91 here in CA.

 

go to a tuner. i had the same problem with my ss at around 17k miles. i descreened my maf at around 10k miles and it started pinging at wot and then i replaced it with a stock one with the screen still intact and it still did it. replaced my fuel filter then plugs and wires and still did it. couldnt understand why so then i went to a tuner and at wot i was pulling 9* of KR he pulled mad timing to combat the KR until it finally stopped but then i had a hell of a lot less timing which sucked. after i got my cam i tuned it again the dudes computer flamed out when it was at 96% loaded. it fried my pcm!! i was pretty pissed but he got me a brand new computer and had it flashed for my car. the thing is that there was a updated file that had a revision for the false KR the the computer was picking up with the old puter and the car runs better than when i got it brand new. i dont know if it makes sense but there it is.


get it tuned by someone or have an updated file for your car flashed to your pcm.