Hello
My 03 with a 5.4 has been hesitating a when you accelerate and cutting out as well as idling rough and die when you slow down. It does all this intermittently. Not every stop or every time you accelerate. I first got a code for the MAF and both banks running rich (PO102, PO172, PO175) so I cleaned the throttle body and MAF. The running rich code came back (PO172, PO175) so I then changed the MAF and air filter . It seemed to help for a day or so then my light came on and I figured the same code was back but to my surprise it was now both banks running lean(PO171, PO174) so I took my MAF back and got another one. It hasn't set a code yet but it is still running poorly. I am looking for ideas.

I have changed all the COP's and plugs as well

Thanks

 

post the actual code number... maybe there are other things to consider.

 

The mistake is not interpreting the codes correctly.
You went into guessing and guessed wrong.
I'm not trying to rub you but to get you to see what the correct way is.
You cannot just go by the first words you see and think it suggests what parts are the cause unless you have previous experience with those codes..
The rich/ lean is the fuel tables shifted out of limits that sets the codes.
.
You have an air leak in the intake system.
.
The OX sensors detects the extra air and tries the 'Richen' up the fuel to compensate but cannot accomplish.
This causes rough idle and stalling.
This is where part of the code description comes from.
Has nothing to do with the Mass Air meter or the throttle body per sey.
Good luck.
.

 

Check the ductwork between the MAF and the throttle body....especially the pleats. Any air leaks in that area that are downstream from the MAF are unmonitored and really screws stuff up.

 

Thanks for your suggestions I will go check for leaks

 

I have not found any leaks at all between the throttle body and MAF or anywhere else for that matter

 

You have not posted the codes.
If they are 171/174 there is an air leak.
Check out the rubber connections behind the throttle body vertical intake part where the PCV is piped to.
Good luck.

 

I will check there as well I did post the codes in the original post
Thanks

 

Yes so you did list the codes.
My over sight.
Good luck.

 

Thanks for the help. I actually added the codes to the post after the first person asked for them they originally wasn't in it. They may not have been there when you first read it and I will need the good luck LOL
Thanks

 

Just an update the new codes that it threw was running rich and MAF he didnt give me the code numbers. They said they wasn't sure what it is but I am suppose to take it back next Monday for some further testing. I am confused why it would go from rich to lean and then back to rich.

 

I took it to the shop they are not sure what is wrong with it yet they unplugged my MAF sensor and said to drive it and see if it messed up. It didn't mess up so I plugged it back in and ran great had good fuel trims and the MAF was reading good. After about 40 miles the MAF readings would be erratic and go to 0.0 then jump all around and the short term fuel trims would run real rich and jump as well. When it did that it started cutting out so I unplugged it and it ran good again. So I plugged it back in it ran good again for about 35-40 miles again and then the MAF readings messed up again. My question is it my MAF or is it something in my computer? I have replaced the MAF but could I have got a Bad part from the auto supply ?
Thanks

 

You said you checked for leaks in and around the intake, but you didn't mention how. When I suspect a vacuum leak or an intake leak, I'll use carb cleaner or ether, and spray around sealing areas on the intake components. While doing this, listen for engine rpm to change suddenly, there's your leak. Also, have you made any recent mods to truck at all, anywhere?

 

I used carb cleaner as you mentioned. I sprayed it on everything I could find while I listened for a change in idle and watched the fuel trims to see if there was any change in them as well.