FastEddie

New to board and have a question in regards to pinging with a 2000 4.8l sierra.I have tried 89 and 93 octane with no success and took timing out with a predator but it still pings under load. Is there something else that would cause this besides timing? I have an airaid cold air and mit along with a throttle body spacer,exhaust and a throttle body hot water bypass on the truck. Any of your help or wisdom would be very appreciated. Please give me some ideas on what to do. Thanks

budhayes3

iTrader: (19)

Could be running a little lean, or possibly carbon deposits. If you have a scan tool you can check out your long term fuel trims, if it's postive, it's lean. If that's OK, you could try doing a top end clean with Seafoam (not a bad idea to do as a maintenance item anyway)

BADDAK

iTrader: (2)

Where can you get Seafoam from?

stall speed

iTrader: (1)

Try fuel filter first,lean conditions WILL cause detonation

dewmanshu

iTrader: (4)

Pinging as in audibal pinging? Or something you are interpretting as pinging on a scanner? 2000's are known for KR...but audible pinging is bad none the less. It defintely means too lean or too much timing. Any codes?

KySilverado

iTrader: (7)

Sticking EGR valve if equipped comes to mind.

02sierraz71_5.3

iTrader: (2)

vacumme leaks can cause spuradic problems Im finding out about that now

budhayes3

iTrader: (19)

I get it from NAPA.