mpjman

So i have a 2008 suburban with the 6.0 motor. Of late when I'm at idle usually i notice it more in gear, i feel the truck running a little rough. I look at the RPM and see it rise a little from the 500 then come right back down.
I had the throttle body cleaned, a full tune up (plugs and wires), replaced the air filter and have run two bottles of injector cleaner through it .

Anyone have any thoughts, they would be greatly appreciated.?


As an aside, and not sure if its related or even abnormal, but occasionally while I'm cruising along on the highway and go to change lanes, and want to a accelerate i find the need to punch the gas causing the RPM's to jump and the truck to take off. If i try lightly pressing on the gas it doesnt seem to really help, until i push much harder.


Thanks all as always

oilcanhenry

Might want to run a scantool on it. 500 RPM's idle when warm seems a bit low to me, but I dont own a Tahoe 6.0L either. Only time anything like that happens with my Malibu, its the damn rubber floor mat being too near or right under the gas pedal when I punch it. Going to have to fix that..My K-1500, when I punch it, it goes every time.

kevinkpk

Low idle can be caused by fuel pressure regulator. Small diaphram with a vacuum hose attached to is. remove the hose, if it has gas in it, the diaphram has a hole in it, and needs replaced.