Dipstick tube replacement, chasing P-0171

[lashidalgo]

Hi there. I'm trying to solve P-0171 in my 02 E-350 V8 5.4L

I've smoke tested the van and found that one of the issues is that the dipstick is leaking at the mounts, the holes are right where the upper bracket joins the tub. The whole weld came off making two holes in the tube.

I'm trying to swap the tube for a new one. Luck was on my side so I was able to pull it from the block without breaking it ... Then I realized I wasn't able to get the tube out since it goes behind the EGR pipe and through the exhaust manifold, the clearance is just not there. What were they thinking !!!
I though about cutting it but then I'll have the same problem installing the new one.

Now Im stuck. I could try putting the old one back in and patch it, but both brackets are broken so I'll have to fab something. Then I found this thread from 2012 ... https://www.sportsmobileforum.com/fo...help-8402.html

Basically I'd have to take the entire exhaust manifold out, which I don't want to do since the studs look pretty rusted and is not leaking.

In that tread, they also mentioned the hack of cutting the new tube and adding a flexible piece of tubing to get it in. This will be my last resource.

Then I discovered they sell braided flexible lines that seem pretty awesome, but I only found one compatible with the 5.4 and it says it needs custom tube headers:
https://www.summitracing.com/parts/mil-22029
I'd really like to go with a flexible one to avoid all the header headaches and the tube hack

Has anyone here done this job and can you share your experience solving these issues?

[carringb]

Mine broke like that too. I just left it until the next my motor mounts were shot which took out a header. I just zip tied the old one. Ran it that way for years, so probably 150,000 miles at least.

[JWA]

Color me slightly confused but I too own several E-Series with the 5.4 motors---I don't quite understand how a leaking dipstick tube would cause or affect DTC P0171. Can I ask how you came to that conclusion?

To my mind since the dipstick is on the left (driver's) side and the P0171 DTC is for Bank 1 aka right (passenger) side leads to my confusion. Even so another of my E-Series with 290+ K miles has the same detached tube, no DTC's relating to Stoich readings, LTFT & STFT's both reading good.

Here's an image of my 2005 E350 w/5.4 motor's dipstick---all is well there too:

[lashidalgo]

Originally Posted by JWA

Color me slightly confused but I too own several E-Series with the 5.4 motors---I don't quite understand how a leaking dipstick tube would cause or affect DTC P0171. Can I ask how you came to that conclusion?

To my mind since the dipstick is on the left (driver's) side and the P0171 DTC is for Bank 1 aka right (passenger) side leads to my confusion. Even so another of my E-Series with 290+ K miles has the same detached tube, no DTC's relating to Stoich readings, LTFT & STFT's both reading good.

Here's an image of my 2005 E350 w/5.4 motor's dipstick---all is well there too:

When i smoke tested it, i realized smoke was coming out from the two holes left by the broken weld. My assumption was that the vacuum leak was affecting the fuel trims. I was confused with the banks and assumed it was one of the issues. You’re right about the banks, either way its gotta be fixed.
Btw I've got 185k miles
Also found...
- leaky booster (to the inside)
- egr when off throwing lots of smoke at the valve and the exhaust pipe connection
- throttle body gasket seems to be leaking where it meets the intake manifold. ( i had a ford dealer change the intake manifold 2 years ago because of the known coolant leak causing missfires. They probably screwed up)

Im determinated to fix them all starting with the booster for security reasons....

[JWA]

The Lean Bank codes can only be set when engine is running and induction air is being drawn across the MAF. While its good to know if you have leaks in the induction system the leaking dipstick tube isn't causing your DTC P0171.

HTH