Hello everyone, my Explorer CEL just came on today, when checked it only brought up a code P0171.
I have read through a bunch of the post and it seems most people get two codes where as I only get one.
Also most say their vehicles run rough, mine runs great, so I am at a loss as to what to check or replace first.
There does seem to be a slight ping when under load. Any help is greatly appreciated.

Thank You

 

Welcome to the forum!

The source of the P0171 could be a leak in one of the intake manifold gaskets for bank 1.

-Rod

 

If there is an intake leak, wouldn't the vehicle run rough?

 

No, but it may PING (running lean)... Philip

 

Just wanted to let anyone know that may have this problem in the future that mine was caused by a cracked pcv line. Took it to the dealer to get it fixed, didnt want to go through the hassle myself. Sure glad it wasn't the intake seals.

Take Care and have a great day!

 

Hello again everyone, wanted to post again on my explorer and see if anyone might know what I need to do for pinging. As I stated in previous post, the pcv line was cracked and dealer replaced it. No CEL anymore, however, I still have the ping under load. Was thinking plugs and wires, but the vehicle only has 69K miles on it. Any suggestions?

Thank You

 

Clean the MAF with SCR, non residue cleaner and reset PCM/ECU.... Philip

 

gr97135. Thanks for posting what you found to be the problem to the code. I have the same code only for both banks. I will check this out first before I replace any gaskets.
The code all started from me trying to get rid of the pinging. I had pinging under load and decided to change the spark plugs. I think the driver rear cylinder plug was very loose, maybe hand tight. I have COP's, don't know if you do, so I didn't have any wires to change. I also put in a K&N air filter and cleaned the MAFS with the right cleaner. I also changed the fuel filter, which I think contributed alot to my problem because the fuel coming out of the "clean" side was brown. But doing this did get rid of my pinging, BUT now I have a P0171/0174 code.