P0174 Code Help

[NickChick]

Hey everybody! So I have been doing some reading around the forum regarding the problem with this code and I still cant seem to narrow it down. First of all, these are my symptoms:
- Code P0174: Fuel System Too Lean (Bank 1)
- Upon start up, only really noticeable when it is cold out and I warm it up in the mornings, it sputters and RPM's jump up and down rapidly and it sounds like it is going to die.
- During idle in park there is almost like a popping sound every 15 seconds or so from the exhaust. If you are sitting in the drivers seat its almost like a short vibration felt in the seat every little while.
- Not sure if the temperature matters but it has been in the negatives for almost the past two weeks.

The truck drives fantastic other than this issue. It has been intermittent the past two years for me. These symptoms only occur during the winter season, never see them in the spring, summer, or fall. There are times where I can reset the code and it wont come back for several months.

Just to let everyone know too, I already checked the PCV system. No cracks in the line anywhere. Both elbows are good and so is the valve.

Just ready to have this issue fixed. It's not a huge problem but I hate whenever my light is on and when my truck sounds like its going to die when its cold. Thanks guys!

 

[thenaaks]

Air is entering the intake somewhere after the MAF. There are half a dozen vacuum lines running to and from the intake. Double check all of them. Plastic lines, rubber connectors. Trace as far as you can see. Listen for a hissing noise if possible. On two 5.4 trucks I've worked on recently, the little lines on the passenger side have been the culprits. You might even have to open up the loom covering to find the leaks.