turboescalade

iTrader: (10)

Hey guys, i have an 07 classic, 5.3 w/112 Maggie, running a 3.4 pulley, pretty mild setup, 5-6 psi stock air intake, same old ****.

The problem I'm having is in 2nd gear under full throttle I'm getting what sounds like marbles in a can, which I've been told is pinging. Although, no codes are triggered nor does my obd2 reader pick up any misfire. I now recently went to Gibson shorty headers, 2.5 exhaust through with x pipe, and went to a tr6 plug but am still having the same issue.

Is there some off beat chance that this sound is my tensioner or am I just being way too optimistic lol.

I thank you for any of your suggestions guys.

AKlowriderZ71

iTrader: (22)

MAF calibration or dirty/bad MAF is a possibility. If it has an oiled air filter, clean the MAF first.

SILVERADO11

Who tuned it? i had the same problem, tryed new TR6 plugs, changed to Chevron fuel, cleaned my MAF, Cleaned and tightend all grounds i could find, installed a cold air intake, installed a 160 thermostat, checked for vacuum leaks, nothing helped. Then i had a local shop dyno tune my truck gained 25HP and 35TQ, gets way better fuel milage, and it feels night and day. The tunner said my stock magie tune was for some resson alittle lean on my truck causing the pinging. Hope this helps

1SlowHoe

iTrader: (28)

Get hooked up to a scanner (Aeroforce gauge/HPT/EFI) See if the PCM is pulling timing and reading KR. If you can hear the marbles in a can, it's probably pinging pretty badly.

Pooki

iTrader: (9)

Was it doing it before the headers and exhaust work J? I still think its a tune issue and can be worked out easily.

Gadgetized

iTrader: (9)

Does this happen all the time? Let the truck warm up, and try it then (as soon as it gets to a good temp). Then drive around and see if it happens worse after some heat soak. Did you change anything since the tune? Something as small as an airbox mod could do this (it could be sucking in warm engine compartment air).

turboescalade

iTrader: (10)

Actually went and got a brand new maf just to eliminate that from the reasons, Ive tried the heating and running trick, I think you guys are right about the tune. I got it goin in as soon as it stops snowing up here. Thanks a lot you guys for your suggestions.