P0171 and P0174 lean codes

[HD4mula]

UPDATE! Problem was the vacuum line on the lower intake, I believe it tees off from the PCV line and runs down, replaced and codes went away, runs great!

So did you remove the SC to do it? Is that definitely the only way? Thanks.

[HD4mula]

Wow! This forum is so much slower than 5-6 yrs ago when I used to be here more time. Anyway, with one of those telescopic cameras I was able to confirm a hole in that elbow on the lower intake manifold. So I'm pretty sure that is the cause of the codes. I think this will happen to most sooner or later. Maybe if you have a good oil separator it may last longer as I found many saying the oil will degrade the elbow faster. So bookmark this thread. The part number for the replacement hose set is YL3Z-6C324-BA. There is also another very similar part#. Cost was $47 at my dealer and it includes all rubber elbows, PCV and all insulated hoses from the SC to the PCV and all the way down to the lower intake. If you don't care about stock originality you can adapt something like a metal elbow with couple pieces of FI hoses. Having the SC intercooler out may be the easier way to replace it but I found at least one at NLOC that removed couple parts on the passenger side and was able to squeeze the hand back there. That's going to be my first try. Some other people used a metal plug and eliminated the elbow. I think that would be the way with an L&S separator. Still I'm not sure about going that way. Just wanted to share my research about this. ;)

[Dan_d_glassman]

Thanks for the part number - helps greatly!

[highflier]

Heres something that happens to me
my # 1222 sits in a hanger alot and after sitting for a month it runs like **** feels like 6 banger shakes stumbles and throws codes 171 and 174.
once I get rid of the bad gas everything is fine. Ive tried all the aftermarket fuel treatments but to no avail

Damn shure not going to let my wife drive it when im gone

[Coumer]

YL3Z-6C324-BA - This was my problem, wish I had read the post sooner. My elbow looked just like the one pictured earlier in this thread. Lean codes - this is most likely the culprit
Thanks,
Bart
I also replaced the large rubber boot connector between the air cleaner and the throttle body it was around $70 at Ford. The oil also made the vacuum elbow blow the boot useless too. The little rubber vacuum elbow is Ford part# E3TZ-9E499-C to save you some time!

[califabricator]

Did anyone or has anyone ever try to use a smoke /fog machine to insure this was the culprit?

[throttle jockey]

Countless trucks over the last 16 years, nearly 17 years (starting with the '99 Lightning) have fallen victim to a ruptured turkey pan elbow as the culprit for the P0171 and P0174 lean codes. This is far from uncharted territory, a smoke machine isn't necessary.

[califabricator]

Yes a smoke machine is not needed.. So there is no way to insure that the rubberized elbow is blown other than removing the blower plenum mid-plate and cooler.. From what I understand the one time use 15-16 bolts that need to be removed and replaced are not cheap and if gasket is chewed, which more than likely it is add that to cost as well.

My question are , due to being so far away from civilization, how far down will the smoke diagnose if pumped into the air box and throttle body propped open? Will it make it down to Pistons? Will it harm the sensors?

Thing is I don't remember that elbow when I did the L&S oil separator or when I did the I/C cleaning..
So I'm guessing it's on the passenger side coming off the pcv which now goes into the oil sep..

[throttle jockey]

So there is no way to insure that the rubberized elbow is blown other than removing the blower plenum mid-plate and cooler.. - You don't have to pull the SC (see pics below) but it makes the task easier, especially if you intend to plug the turkey pan.

From what I understand the one time use 15-16 bolts that need to be removed and replaced are not cheap and if gasket is chewed, which more than likely it is add that to cost as well. - There are no TTY bolts to be replaced and I've never heard of anyone damaging the midplate gasket who took their time when removing the SC. I've never replaced a midplate gasket and I've pulled the SC on both of my trucks multiple times.

My question are , due to being so far away from civilization, how far down will the smoke diagnose if pumped into the air box and throttle body propped open? Will it make it down to Pistons? Will it harm the sensors? - Nothing will be damaged.

Thing is I don't remember that elbow when I did the L&S oil separator or when I did the I/C cleaning..
So I'm guessing it's on the passenger side coming off the pcv which now goes into the oil sep.. - The L&S separator doesn't replace the turkey pan elbow, it simply caps off that particular line. If/when the elbow fails you have a vacuum/boost leak. See the attached pic below to see where the turkey pan elbow is located. I've also attached a link to a Lightning Rodder thread showing how to plug the turkey pan and eliminate that elbow for good.

OldTimer's Turkey Pan Elbow Delete How-To

Intake.jpg

Lower Plenum Elbow Exterior.jpg

Lower Plenum Elbow Fitting.jpg

Lower Plenum Elbow.jpg

Lower Plenum Fitting.jpg

Lower Plenum PCV Line Intact.jpg

Stew-Lower Plenum A.jpg

Stew-Lower Plenum B.jpg

Stew-Lower Plenum C.jpg

[califabricator]

Hahaha , look men, the smoke machine was a good idea for whoever can use its powers, yes I did try it and could not get smoke to show me where the leak was... Yes the oil separator from L&S is definitely an excellent mod, that was one of the first things I did after I took my eaton to stieg's for the latest stage while I was Stationed in Ft Leonardwood Mo.
The L&S separator kit does come with a plug to cap the line, but if can remember correctly I think I used that cap for not being able to find the elbow behind the intake.
While I was removing the upper blower an plenum I noticed the tube from the back of intake didn't have the cap that's provided, by then it was too late to turn back.

Anyways, for all the dudes looking to attemp this, it's not as bad as it seems..
Bad thing was I didn't have the 11/16 ratcheting box end wrench I thought I had..
So I went with what I know, needle nose vise grips.. Yes some might say that would be harder but actually not..
Just used them to break the fitting loose so I can jam an Allen wrench in from the front side and out it came, just like Flynn my friend. No hard time, no arm scrapes, not difficult at all..

Now when I did the cleaning for my I/C the first I used carb/break cleaner.
As I'm looking at my I/C now I'm thinking I should have had it hot tanked .. Any thoughts..? Otherwise I'm gonna use easy off this time and be done with.
Good thing is now I can do the delete mod and clean my I/C again.

Thanks gentlemen I just hope the p0171 is gone once I re-install everything.

[califabricator]

[califabricator]

Update w/question:

So I did the delete and replaced it with the 3/8" npt plug and re-installed everything, did a decent test drive and the check engine light is stil displayed.

So will a complete drive cycle re-set the check engine light or does the battery have to be disconnected while making the corrections or any repairs to the trouble code?

My next repair solution will be to replace the seals on all my fuel injectors, they are stock so if anyone knows the part numbers or where to get them for stock injectors that would be most helpful. Or the O2 sensors ...

What I'm gonna do is disconnect battery to reset the code and if it comes back move to the next solution..

Any help or ideas are welcomed

[GRANTBP]

Scan it and clear the codes

[califabricator]

Yes I thought about that, just delete the codes and see if it comes back..
Instead I checked the pcv and the L&S separator and it was full of white crud, something like sludge, was wondering how to clean them them, didn't think the filter element was conducive to break cleaner .. Anyways gonna get a new pcv valve and replace the 3/8" 1/2" & 5/8" hoses on the passenger side for now.
Also order the two O2 sensors & injector seals. I tried scanning it and still has the p0171/174 codes , we'll see what happens..

I also ordered the power train & Emision manual to help .. Does anyone know if it's any good ?

[GRANTBP]

Clean it up mine did that when the season change it will be ok