Was getting the P0171 and P0174 lean codes. Truck still running fine. Put in a new maf and those codes are gone but now getting the P0113 IAT sensor code. Some funny starts but running fine since new maf

 

I believe the IAT is part of the MAF.......

 

Yes, that’s the case with my truck. So why would a brand new IAT be coding?

 

Aftermarket brand?

 

Yes

 

I tool the DNA brand maf out and noticed that one of the elements is missing. 😂 That will be getting returned. Put the original one back in after a thorough spraying with maf cleaner and so far so good. Only drove it around the block though.

 

So the P0171 and P0174 came back. I ended up taking it to a mechanic. He did a smoke test which revealed the line running from the vapor management valve to the intake manifold was leaking bad. I didn't even realize that that was a vacuum line(there was a plastic protective sheathing on it which concealed the fact that it was a vacuum line). Ford had some weird quick connect fittings on each end of a molded hose. I just replaced it with a hose of the same i.d. and a couple of small hose clamps and called it a day. I've ran through a tank of gas and it's all good now!