truck missing at low to mid rpm

[catone]

truck runs like shit at low to mid rpm then runs fine at 70

 

[generic]

When you say 'missing', are you getting misfire codes? Without more detail, it could be any of a number of issues at this point. Mine was doing this for a while when I was commuting 800mi/wk and eventually got worse as in losing power on hills and dying at stops while in gear. I've been steadily working through a list of things to check/clean/replace:

Fuel filter (replace)
MAF sensor (clean first, replace last)
Check for vacuum leaks
Pull spark plugs and inspect/replace
Clean throttle body
IAC valve (inspect, clean, replace)
Replace intake plenum gaskets
Check for vacuum leaks
PCV valve (replace)
EGR components (inspect, clean, test, replace)
Check for vacuum leaks
Evap system (inspect, test, replace)
Fuel rail gasket(s) (inspect, replace)
Fuel injectors & seals (inspect, test, clean, replace)
Oh and check for vacuum leaks.

I discovered my fuel rail gaskets were blown out and am replacing those now, will find out soon enough if that was the problem.