po174 po171 heeellllp

[jawknee99]

Heres the deal.
150,000 miles on my explorer running great until i got the famous po171 po174 codes.
Had my truck sitting for a good while then finally
Changed my#
Coil#pack,#spark #plugs#wires,#spark plugs. Oil,#oil #filter#air#filter#and of course your#intake#gasket. Something told me to change the injectors but figured. Hey my car cant be that much in bad shape. Put everything back together what do you know. Worst engine performance ever. No power misfiring, car as red and got. Thinking i had the wrong firing order double checked triple checked. I had it right.#
There i go to change my cats only changed 2 btw...the big ones. Coming back home a little better but still no power. I knew i should've changed my injectors since day 1. New injectors plus new gasket under the fuel rail. Btw all my#gaskets#were im really good shape so are all of my vacuum and evap hoses.
So now here i am with a ton of new#parts. Got the#fuel#filter#but couldnt get it off . Couldnt wait till the auto store opened so i figured hey what the heck. Turned it on runs like hell again full power. Everythings good till i get those damn codes again.
Finally changed the#fuel#filter#which was dirty af. Ran it more same codes.
I smoked out my intake with a homemade machine and no leaks from any places ...im stuck now what... help

 

[Turdle]

are you certain the Fuel pressure is good?

In a pinch an inexpensive dial type tire pressure gauge will do. Push it onto the schrader valve while the engine is running. You should have 60 psi. Beware some fuel will squirt out when you remove the gauge, so do it fast, both on and off.

Don't hesistate, push it on and hold it down tight. Get your reading, and pull it off real fast.

If the Fuel pressure is good, then chances are non metered air is getting in somewhere behind ( downstream) of the MAF.
There is a pcv vent hose , also the main air tube could be cracked. Did you change the lower intake manifold gasket between manifold and heads?

 

[jawknee99]

update

Went to a shop that around my house. Asked the man to check my fuel pressure. It read 40 with the koer. So im guessing my fuel pump is done with. Any tips on changin it on my 4.0l ohv...
Or can that fuel damper play a role in this mess????

 

[swshawaii]

Just for kicks clean the MAF sensor filaments with electrical contact cleaner BEFORE dropping the fuel tank.

Codes P0171 and P0174 (See post #3 )
http://www.explorerforum.com/forums/showthread.php?t=233044

 

[jawknee99]

Already did twice.
Even the guy that checked my fuel pressure thought the same.
We both looked like fools when the pressure readings came in

 

[Macgiobuin]

Forward Catalytic converter (one of them) broke down and got blown down to the common downstream catalytic converter. After it stalls and then cools, the powdered ceramic material falls down and suddenly you can run again. Separate the input pipe that goes into the downstream (common) converter, and if the common converter is full of cat junk, that's your problem. But which one upstream failed? And why did it fail? Possibly a bad fuel injector, either stuck open (causing a rich condition, which the computer tries to fix by starving all 3 cylinders on that bank of fuel), or stuck closed, (causing the computer to fix by richening up all 3 cylinders, which leaves 2 cylinders running real rich, causing the cat on that side to burn up and disintegrate.) Nevertheless, check the downstream converter for being clogged. I pulled mine off and turned it input side down and a pile of junk came down like an avalanche. So if you replace it with a new one, now will it happen again? Here's where you gotta check for bad fuel injectors, bad fuel pressure regulator/housing....

 

[jawknee99]

Changed cats and injectors already.
Just have low pressure on my fuel
40 psi while engine is running

 

[Macgiobuin]

40 psi is not enough. Had same problem; P0171 and P0174;Low fuel pressure: only 17 psi and it should be 60-70 psi; changed pump still got only 17 psi. Took down the tank (again) and put the gauge directly on the output pipe. Still only 17 psi. I extracted all the bolts holding the pump assembly and fed 12 V to the black and red wires in the harness. With a flashlight peering in, I lifted the assembly just enough to see the top of the actual pump and I saw that the regulator was spewing fuel from fatigue cracks all over the black plastic housing. These cracks were microscopic and virtually impossible to detect without it actually running. (This can be very dangerous especially if you're a smoker, duh) I found the problem. I've seen others where the problem was a cracked hose in the assembly. (there are 2, one from the pump to the reg and one from the reg to the output pipe) Now how can I get a regulator/housing without buying the whole assembly? I don't need a pump. So I looked at the regulator and saw that the regulator (not its housing) itself will last forever, it's just that cheap plastic housing that's bad. The pull-it yard I went to had a few explorers but all 3 that still had a tank had tanks that were inaccessible--no wheels, laying on mud, and no they ain't gonna topple the car for a regulator. So I made a housing out of copper pipe and brass fittings and a propane soldering job. 62 psi! Now, it'll last forever.

 

[intelisevil]

so i made a housing out of copper pipe and brass fittings and a propane soldering job. 62 psi! Now, it'll last forever.

Pictures!!!

 

[Macgiobuin]

Picture of the fuelzilla:
https://www.flickr.com/photos/136039478@N07/24666642413/in/dateposted-public/

 

[jawknee99]

Update
Ended up being my pump and injectors oh well at least I know everything is brand new well everything except I need all 4 cats been running it straight
Thanks the help