I have an 06 5.4l with lean codes for both banks I have replaced the MAF and replaced the fuel filter. I replaced both cat's and oxygen sensors. I have 130,000 miles in the truck. I checked all vacuum lines (I think) for leaks and make sure all are connected. I have loss of power above 1/4
Throttle and horrible mpg's. Sometimes I'll have a miss fire in one cylinder but it goes away. I have been told to replace the intake manifold gaskets. If I replace the gaskets what do I need and what is the info I need to know like tourque for bolts if I need coolant etc. I need to figure this out cause I am moving from New Jersey to Colorado soon and I'm driving there. Please someone at least take a look. This is my 3rd attempt at asking for help.

 

PCV elbow was my v10's issue. Another potential for it is the throttle body gaskets. I would pull the PCV. Your at 130k. It needed replacing along with the PCV valve at 100k

 

Question. When the codes came up were you low on fuel??

 

And also after doing all. This. You unplugged the battery for like ten minutes or whatever to reset things right? It's essential to do that cause you could have fixed the problem and not even know it.

 

I have no vacuum leaks and I think I found the problem. The wiring to the maf at the plug when wiggled the truck shuts off. I have to replace that first. I have reset the truck 3 times since I replaced the MAF and it always comes back. I talked to a ford tech today and he said that the bad connection to the MAF can cause the lean codes. I will change the plug and let you know whats going on. Thanks

 

Definitely. The MAF is the problem from what it sounds like the wiring can go bad from what I hear

 

I now have p2106 and it sounds like I now need a throttle body. Wtf! I wish I still had my 6.0.

 

Well, I can tell ya the experiences I had over the weekend trying to fix the same problem you're having:
I started with 10 codes (incl 0174 & 0171)on my 99 E250 5.4 and extreme loss of power above 1/4 throttle. First I changed #6 coil which cleared the misfire codes. Then fuel filter and a couple vac lines which were old and cracked. Still no change in performance but down to 4 codes. Next came cleaning the MAF, which made no difference. So I replaced the MAF, but still no go.
I thought maybe my cat was clogged, so I pulled out one of the O2 sensors and fired up the van, thinking the gases could escape through the open hole allowing it to run better. Nope.
Ok so now I'm wondering if the empty O2 hole is big enough to make a difference. I next separated the cat from the y pipe and lowered the cat enough to fire it up. Still no go, so the cat is ok.
At this point, I tried a new approach by purchasing a fuel pressure tester. With 22psi at the rail, I knew something else was at fault. At this point I'm getting frustrated and desperate with less than a day to get this van going before needing it for work this morning. Another trip to AAP for a fuel pressure regulator. No dice.
As a final attempt, I dropped the tank and put in a new pump and filter sock. BINGO! Back to normal and the codes went away!
I never suspected the pump because in my experience, the pump usually just quits. Done. Kaput.
I should note that the in-tank filter sock appeared very dirty. Whether it or the pump was at fault, I'll never know. At that point I was throwing parts at it in hopes of SOMETHING working.
If you haven't done so already, I suggest testing fuel pressure. If I'd done that in the beginning, I could've saved myself a lot of time & money.
Good luck, I hope this helps.
Rich

 

I have a sneaky suspension that it may be a problem but in getting 39.2 to 40.6 psi. It dose drop to 38.5 psi but not very often. I have had both cat's replaced about 2 months ago cause they were faulty. I cleared the codes by disconnecting the battery and About 2 hours later I took it around the block did not go into limp mode but since I live in New Jersey I am out plowing snow today so tomorrow I will be taking it for a ride to see how it is. Is it pretty easy to do the pump? Is there a special or specific tool I may need.

 

First understand that I am no expert. I'm a fair shade tree mechanic at best. My problem could be different than yours, but it matched the symptoms you described, so I threw in my 2 cents worth. And to be clear, I never got a 2106 code. But I've learned that one simple problem can throw a lot of different codes.
I used the "keep throwing parts at it until it works" approach, and ended up spending about $150 more than needed to find the problem. That money may have been better spent at a shop with diagnostic equipment. But I'm cheap & stubborn, and kept making stabs at it lol.
The specs for my van said 30-40 psi is ok, so when I got 22psi, it was clear I had a problem. Yours seems to fall in line with where it should be, but I'd check for your specific vehicle specs to be sure. My van is a 99, so there could be differences.
To answer your question, changing the pump was simple enough. Not a hard job for the average wrencher. Ive done it by myself, but having a helper is a plus. Place a jack under the tank. Two straps holding the tank up. I did snap one of the rusted strap bolts, but just welded a new bolt onto the broken end of the old one. Once the tank was lowered enough, I was able to remove the pump assembly from the tank and swap out the pump & sock in the assembly. On some vehicles, the assembly is held in by bolts, others have a round wedge type clamp seal. You'll probably need a special tool to remove the fuel lines. It should be the same tool you used to change the filter.
Do a little more research on your code before listening to me though. I'd hate to steer you in the wrong direction.

 

HAHAHAHAHA

That made my night.....Ford themselves couldnt pay me to own one lol

 

WHen I had your codes O'Reilly gave me a plethera of potential problems that can arise, I recommend going through that list. Ask them for information on your two codes, they will print you off some paper with a ****load of diagnostic material.

 

Had the exact problem on 01 5.4 eddie b expy today. Threw both bank lean codes. Took out air filter and then maf and cleaned. Put maf in and taped around rubber grommet wires go through. Made sure air filter gasket was in place and traced all
Joints to intake making sure all was well. I then started waited for it to idle at op temp and sprayed carb cleaner at pcv valve hoses and every hose leadi
G to intake. No idle change so no vac leaks. So i shut off n reset ses light by unhooking batt. Problem is gone. If you have for sure done all
Thos Try testing the four wires on maf sensor . Possible bad ground. Or low volt. Look up online how to test and for wires colors.

 

Well i had a vacuum leak. I had to replace an elbow in the back of the motor above the trans. It's the same elbow that the 150 ' s were recalled for. Any who it has been replaced running better but still getting bank 2 lean. Its been 1 day since fixed. I guess it's one step closer to fixing my problem. Just getting really annoyed with this.

 

I just got code p2112. Anyone get this code before