P0171 (System too lean bank 1), P0174 (System too lean bank 2)
 

I keep getting these 2 CEL codes. Ive already replaced the fuel filter. The truck doesnt start hard, doesnt lack power and isnt backfiring.

These are really common. It is usually the PCV hose elbows that are cracked and sucking air, especially the one that connects to the rear of the intake manifold. The other common cause is a dirty MAF sensor.

Cool. I'll have to look into those 2 things. Thanks.

1: low fuel pressure
2: intake/vacuum leak
3: dirty/bad MAF sensor

check the small 1/4 inch vacuum hoses on the drivers side on teh motor above the valve cover. i had 2-3 hot spots that caused the rubber to crack after 5 years... same code.

One of the elbows had a little hole in it. Its looks like over time the rubber just got soft and cracked, causing the hole. I found a piece of hard rubber hose in my garage that is the same size and at least for now thats the fix I went with.
The truck seems to idle a lot smoother, so hopefully thats all it was.

I just went through exactly the same thing, only I replaced the MAF sensor...for nothing. The part you're looking for can be found at a dealer for about $30. The repair took about two minutes....not even time enough to finish my beer.

advance auto parts carrys that elbow now...A LOT cheaper!

$30??? :eek: Whats it made out of...gold?!? I see that Napa lists it for $3.

The dealer probably seels the whole assembly. Elbows, plastic tubing and PCV valve. That is what they installed on my 01 when it happened under warranty @ 32K miles.

that's correct LxMan1.

I when to NAPA and advanced and no one knew or could find what I was looking for. Anyone got the part number so I can take it with me? Its starting to p*ss me off starting the truck at every stop light.

Ron W., a very knowledgeable source, wrote this for me before I got mine from a dealer:

the Ford part number should be F75Z-6C324-JA and will cost you about $30.00 with the tax

I know what you mean about the stalling..but $30 and two minutes of my time and it was fixed. Good luck!

I've been called alot of things but that ain't any of them.:-missingt

I'm not a tech, just an ex-parts manager/warranty administator and still a do it your selfer. Glad I could help. :-drink

Do it your selfer is definitely the way to go. That simple little repair, in many shops, would've cost well over $100, I'm sure. This website is priceless!! Ron W, this Bud's for you.