PCM update question

bigsid · June 1, 2005

Hey guys, I have a '05 2500HD that I recently took to the dealer because of bad pinging. The mechanic heard the pinging (amazing in itself) and said a PCM update that GM recently released would probably fix it. He installed the update and no problems, pinging seems to be gone. He said GM didn't tell them everything the update changed, does anyone happen to know what all the PCM update changed? I'm really curious now to find out what was changed on my truck after the update was installed. Thanks for any input

Butch 02 Denali · June 2, 2005

The update basicly reduces the overall timing a few degrees. Did they try cleaning the mafs first?

bigsid · June 2, 2005

The update basicly reduces the overall timing a few degrees. Did they try cleaning the mafs first?

<{POST_SNAPBACK}>

Nope, they took it for a drive, said they heard some pinging too and then just installed the update. The truck only has 3500 miles, maybe that's why. I haven't really noticed any change in power, I wonder if this change in timing hurt the power any. Thanks for responding