Couple code's..

[77mud]

I'm currently working on my mothers 2000 Expedition with 5.4, it has 2 code's P0171 and P0174 for bank 1 and 2 lean. so far Ive checked the MAF and it has a little dusty but nothing terrible it also had one of those "tornado" things in the intake pipe that i assume has been there since she got it and its had 200k put on it since then so i don't see that causing it. Ive checked the complete air intake for looseness and tightened everything up. Also checked the PVC elbows and could not find a leak there either, we did put it on a computer that a friend has and only real thing he could see looking at live data was a messed up bank 2 down stream sensor, i popped it out and it was definitely nasty, I noticed that 2 of the wires were worn bare on it so I replaced it, code stayed off about 2 days and came back, haven't had a chance to put it on the computer again though.

Any other idea's to check before she takes it in somewhere to have it checked out? it really has no loss of power or any noticeable problem other that the SES light.

Thanks.

 

[KWT2000]

there is a tech thread here about that it is most likely the elbow for the pcv line at the back of the intake manifold very common problem

 

[KWT2000]

here is the thread for that problem http://www.expeditionforum.com/f48/rough-idle-cel-p0171-p0174-some-simple-things-check-first-10745/

 

[77mud]

I checked those elbows, I didnt physically pull it off because it seemed everyone who did ripped it, but most people said you could feel the vacuum leak with it running and i did not, also I assume the air controls on it are controlled by vacuum? when i had a leak on my 97 F150 id loose vents and it would default to defrost but hers dont do that no matter how hard you accelerate.

 

[KWT2000]

the pcv elbow being bad will have no effect on the vents

 

[77mud]

okay, ill try to get it off the back of the intake and with out destroying an see if it is bad. Forgot to mention the radiator blew about the same time as the code cam on but they are not sure if it happened before during or after the radiator let go.

 

[KWT2000]

i would just feel it first and see if is soft rotten feeling

 

[77mud]

should it feel hard or should it have a soft feeling to it?

 

[Lane24]

Probably not your elbow. You would definatley notice it if it was your elbow. You wouldn't just be throwing codes, the truck would idle poorly. Just moving it around while idling, or putting your fingers over it would cause the engine to start running smooth.

So if you are not noticing a rough idle, did you check just check your MAF or actually clean it? That's where I would guess your code is coming from. Takes five minutes to do. Might as well give it a shot of cleaner. I'm sure you know how to do it, but if not, here's a copy/paste from the tech thread...


Just disconnect your air inlet tube ahead of the sensor, and spray some MAF cleaner through the screen at the little elements in the center of the sensor. Let it sit for 5 minutes or so...,give it another shot, let it sit for another 5 minutes, then start your engine. Some people just use electronics cleaner, but I recommend actual MAF cleaner from the auto parts store. You can also take the sensor right out and clean it that way too, but it's easiest to just spray it where it is. You can hold a rag or something behind it.

 

[77mud]

I wiped it down just to get some dust off it but that's it, ill pick some MAF Cleaner up and spray it down tomorrow if i get a chance. I felt around the elbow with it running again while the engine was cold so the heater hose's didn't burn me and felt nothing and the idle was not affected. the truck has no drive ability issues so I'm sure it is something simple somewhere.