scothron3

i might not be in the right section but im sure someone can help me here. i have a 2007 yukon denali with th 6.2L vortec and it will turn over but wont start. if i pump the gas hard it will start but run terrible.
things ive done....
1. checked fule presure at rail 55 ppunds. turn key and starting.
2. checked fire and spark plugs. good.
3. pluged obdII scanner in and read misfire,
also have service stabilitrac flashing on and off.
4. changed crank position sensor.
before it did this it would idle bad sometimes for a short time then clear up. sometimes it would die at redlights very rarely.

anyone have these problems?
and help would be appreciated thanks!

thunderstruck507

iTrader: (18)

Have you checked throttle position sensor and coolant sensor?

CO99Z28Vert

iTrader: (30)

Have a K&N filter? Regardless check your MAF sensor, clean and or replace it.