2002 Explorer Sport P0174 likely causes

[Taxhero]

I bought an 02 Explorer sport from my cousin. 4.0 L engine, 4wd. It sat for 2 years without being started, so added some fuel system cleaner and gas before starting it. Started with no problem. After driving it for about a week, I got the code coming up. I replaced the PCV hose, as it had a lot of dry rot. Cleared the codes, drove it again, and the code came up again. I then cleaned the MAF and cleared the codes. Though the check engine light didn’t come back on, I checked the codes after driving it, and it had a P0174 pending. I realized that it seemed to give the code during full throttle, and I’ve never had any type of idle problems, so hasn’t acted like a vacuum leak. In fact, the only symptom I’ve had is the check engine light. The other thing that gets me is I’m only getting the code for bank 2, never getting any code for bank 1, making me think it’s more than just a vacuum leak.

Is there any type of known issue about this, or most likely culprit beyond what I’ve tried?

 

[rtk11]

Try running some fuel system cleaner through it. Just a guess, but could be the fuel injector(s) are gummed up in bank 2 and isn't able to provide full fuel flow during full throttle?

 

[Stynx]

Would an oxygen sensor issue cause this?

 

[Fix4Dirt]

yep o2s can cause that... is there a bank 2 air leak from the intake gaskets? could be that under normal condition the leak is so small that the difference isnt noticible, only under WOT

 

[Taxhero]

Try running some fuel system cleaner through it. Just a guess, but could be the fuel injector(s) are gummed up in bank 2 and isn't able to provide full fuel flow during full throttle?

I actually tried that, twice. Since it sat awhile I immediately put some in and added another bottle when I fueled a second time. It was my first thought was a fuel injector, which it could be, but they cost $50 each, so making certain before throwing parts at it

 

[Taxhero]

yep o2s can cause that... is there a bank 2 air leak from the intake gaskets? could be that under normal condition the leak is so small that the difference isnt noticible, only under WOT

It’s unlikely it’s an o2 sensor, because if they give a bad reading they most often will give a different code, though it is possible, it’s usually the last thing that would cause this code

 

[Fix4Dirt]

any intake leaks? whats fuel pressure like?

 

[Taxhero]

any intake leaks? whats fuel pressure like?

I finally got a fuel pressure gauge and plan to test this weekend. The thing went almost a month without the code tripping, then finally did. I decided to drive it with the real time reading displaying on my tool. Fuel trim looked perfectly fine, so I’m really baffled now

 

[Fix4Dirt]

I finally got a fuel pressure gauge and plan to test this weekend. The thing went almost a month without the code tripping, then finally did. I decided to drive it with the real time reading displaying on my tool. Fuel trim looked perfectly fine, so I’m really baffled now

interesting! let me know what fuel pressure is like, happy long weekend!!!! i got finals next week so not so happy

 

[410Fortune]

P0174 with a sohc engine is almost always leaky intake o rings

Yours is intermittent now but eventually will become p0171 and p0174 as the leak gets worse

 

[Taxhero]

P0174 with a sohc engine is almost always leaky intake o rings

Yours is intermittent now but eventually will become p0171 and p0174 as the leak gets worse

I’ve noticed the p0171 tends to be pending. Last time the code tripped I cleaned the MAF again. This time there was a seed from cheet grass that got in somehow, must have gotten blown in by the wind when I checked my air cleaner, or maybe been there all along, it was lodged in there pretty good and too some work for it to come out by spraying cleaner in there.