Fuel Filter Location and Misfire/rich fuel questions

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MarkEMS3

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Ok I have been lying under my ride (2005) trying to find the fuel filter and have been unable to do so.... please tell me where to look. I understand there is suppose to be a door type thing covering it but have been unable to locate, and do I need any special tool to change...

Right now I'm chasing my tail trying to fix this thing. It started with Cylinder misfire codes for Cyl 3 and 4, so I replaced the COP's but was unable to get the spark plugs to turn out so still on the old plugs... This stopped my check engine light and it ran good for bout 50 miles then started missing again and running rich smell. Stopped ran code said Bank 1 02 sensor, so I replaced it (I hope, bank one is by the front drive shaft in front of the cat correct? there isnt another one higher up that I could see.

So reset my light, ran it 20 miles light back on, reading Cyl 3 & 4 misfires, Bank 1 o2 to rich.... so upon suggestion from my buddy I ran a high dose of injector cleaner as he thought i could have a build up on the injectors. This has allowed it to sometimes run fine with engine light still on, but no stuttering or lack of power, but has not helped with the fact that I have to hold the gas pedal down to start it. And sometimes it runs like dog, stuttering and smelling like raw fuel...

What do I do? Should I replace that Fuel Pump Driver Module? Injectors? It has 124,000 miles.... How do I know if its the Drive Module on the frame rail or the fuel pump itself?

The articles I've read show that if my injectors are running rich im gonna kill my engine, and the other articles show it to be relatively easy to do my injectors...

And lastly.... any tricks to changing these plugs and getting them out? I certainly dont need to break on off but to date over past 6 months I've replaced Cyl 1, 2, 3, 4 COP but only Cyl 1 spark plug. I'm thinking once i get this fuel problem done I am just going to get all other 7 plugs done and the other 4 COP's put in and hope she decides to start running good since I still owe a boatload on this Expy.

Thanks
 

darmahsd

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Tucked up behind a plastic cover in front of the fuel tank under driver's side of truck.
You will probably break off the two mounting bolts holding the cover if the filter has never been changed before.
They rust solid to the speed nuts, a brilliant design. You can get new inserts from Ford, then use stainless fasteners or plenty of antiseize so you can get them off again. That cover is the only thing that holds the filter, no mounting clamp. There's a writeup I did somewhere on the forum about my experience with the fuel pump control module. It sits on a bracket on the frame rail behind the driver side rear wheel. Good chance it's the problem whether you're throwing codes or not. Mine wasn't and just stopped running one day. Dissimilar metals cause the unit to corrode through, exposing the PC board to road splash from that rear wheel, creating all sorts of problems. Very common problem on F150's too. $55. from Amazon (Dormans). Includes rubber isolators which separates the alloy box from the steel bracket, preventing the oxidation from breaking through the box again. Another brilliant Ford design where they locate the thing, and they will ask at least $125 for the same unit as the one from Amazon. Good luck.
 
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MarkEMS3

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Went and ran codes again showing bank 1 rich and possible fuel pressure problems. Auto zone $109 for the fuel driver unit, rock auto with next day overnight shipping $79 so it will be here friday. Hope this fixes the problem if not I will be doing the MAF sensor as well and will be under it Friday or Saturday to do fuel filter
 

01yellerCobra

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You need to fix the misfire first. A misfire can cause a rich condition which will cause the code for the O2 sensor to pop. 124K is way too many miles on those plugs. You need to change them out ASAP.
 
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MarkEMS3

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Since replacing the 2 COP's last thursday only 1 time has the misfire code been sent for 3 & 4 since then, and it was only briefly within 50 miles of putting the new COPs on, been just a constant code for Bank 1 to rich. I do know I need to change the plugs, problem has been that they are in there tight and when trying to change them with the COP they wouldnt budge, granted the engine was a bit warm I may try to do it with the engine cold and see but if I snap one off its game over for me. But its on the list to do this month.
 

toms89

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You need to fix the misfire first. A misfire can cause a rich condition which will cause the code for the O2 sensor to pop. 124K is way too many miles on those plugs. You need to change them out ASAP.

Generally misfire reads as lean. The O2 sensor measure O2 content and a misfire will introduce unburned O2 into the exhaust. Rich mixture has low O2 content but this is usually not a result of a misfire.

I would guess there is a fuel pressure or fuel control issue.
 

toms89

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Bank 1 is the passenger side. It may be that the misfire is a result of it running too rich?!
 

01yellerCobra

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Generally misfire reads as lean. The O2 sensor measure O2 content and a misfire will introduce unburned O2 into the exhaust. Rich mixture has low O2 content but this is usually not a result of a misfire.

I would guess there is a fuel pressure or fuel control issue.

I knew that too. Just had it backwards.

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toms89

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I knew that too. Just had it backwards.

Misspelling brought to you by Tapatalk

Easy to do. :)

But I do believe it is a common misconception that misfire would read rich because of the extra fuel introduced into the exhaust. But O2 sensors do not measure fuel. They measure O2 content.. go figure...lol..
 
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MarkEMS3

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Does passenger side bank 1 mean I changed the wrong 02 sensor, I only seen the 1 right b4 the cat and that's the one I changed
 

toms89

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Does passenger side bank 1 mean I changed the wrong 02 sensor, I only seen the 1 right b4 the cat and that's the one I changed

Bank 1 is passenger side, Bank 2 drivers side. Nothing to do with front or rear sensor. Rear O2 sensor codes generally have to do with cats inefficiency. Front O2's are used by the pcm to "tune" air/fuel ratio. What was the numeric code?
 
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MarkEMS3

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HO2S11

I know which sensor I changed and it was underneath the driver side of vehicle, near the front drive shaft and control arm area, infront of the cat and am wondering if I changed the wrong sensor, Im searching currently online for the location of Bank 1 sensor 1 and I found something saying passenger side, near frame by the front inner fender, is this correct?
 

toms89

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HO2S11

I know which sensor I changed and it was underneath the driver side of vehicle, near the front drive shaft and control arm area, infront of the cat and am wondering if I changed the wrong sensor, Im searching currently online for the location of Bank 1 sensor 1 and I found something saying passenger side, near frame by the front inner fender, is this correct?

Bank 1, sensor 1 is the front (closest to engine) passenger side.

Bank 1 is the side with the number 1 cylinder. Cylinder number 1 through 4 is on the passenger side. Make sense?
Sensor 1 is closest to engine on that bank (upstream) . Sensor 2 would be furthest on that bank (downstream).
 
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toms89

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From what I saw online that is a code for bank 1, sensor 1 O2 sensor heater circuit bad. Replacing that O2 sensor may take care of all of your issues.
 
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MarkEMS3

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Well 2 hours later I swapped the O2 sensor from the driver side to the passenger side... Ford Designers/Engineers SUCK... the actual connector was tucked way up in and I could barely get a finger on it, used a screw driver to release the tab and get the old out, then spend 1.5 hours trying to hook into the connector blind, finally pulled it off its mounting clip and was able to get it in. Fired it up but still smelled like raw fuel and rough idle but only ran it a few minutes to get it out the garage and around the block... Will know and post more tomorrow when I run it down the road.
 
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MarkEMS3

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Replaced fuel pressure driver a bit ago... no better and was unable to get the old one off to see if it was corroded thru. Found the fuel filter and got the spring release things will do that in morning if no better its gonna have to go to a shop as I'm out of ideas
 
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