My sel came on and I went and checked it at O'reilly's and the code it gave me was PO171 and PO174. And i have no idea what it is for sure the o2 sensors or what. i would just like to be ceartain. thanks.

 

Do you mean CEL as in check engine light? I have no clue what sel would stand for.

 

service engine light=sel.....A P0171 lean code for bank 1 is the cylinder bank on the RIGHT (passenger) side of the engine
A P0174 lean code for bank 2 is the cylinder bank on the LEFT (driver) side of the engine
could be dirty maf sensor.....vaccum leak... EGR differential pressure sensor...fuel filter..
im sure more guys on here know more about this than i do... but theres a start

 

check the PCV elbow at the back of the intake for cracks. follow the tube from the passenger side valve cover to the back of the engine and u will find the elbow im talking about.

 

On the older '97-'03 + Heritage F150s, it had a nice light that said, "Service Engine Soon".

On the '05-'08 F150s, it has a stupid symbol that looks like an engine if there is a problem with the engine and there is another really stupid symbol (that some mistake for an oil change light) that shows a flare nut wrench for problems associated with the electronic throttle body.

However, I would do what they said above and check the PCV elbow and check the valve too. The PCV valve is a 1 way valve and it should be checked every 30k. But they are like $~40 at a Ford dealer but it seriously takes like 1 minute to put a new on one, just as long as putting on a new elbow and stuff. The engine really isn't that hard to work on which makes it great.

 

I got an 03 v-6 and it has the heated pcv. That one isn't in the valve cover it's just behind the throtle plate on the passenger side. Has 2 little hoses from the manifold and the regular one from the valve cover. The boot that connects the plastic pipe to the pcv had a hole in the back, check that out. Also it's probably better if you take out the pcv when the motor is cold so it doesn't squirt coolant at you. I suspect that the o-ring is junk on mine too cause i can't seem to get rid of those codes. Good luck!

 

If it is the pcv elbow you can get one at any parts store in the "HELP" section for about $3.00.