More P0171 and P0174 codes!!!

[elgato]

2004 Ranger Edge 3.0, Auto, 36,000 miles. Everything stock.

Truck throws P0171 and P0174 codes as soon as it warms up.
(Lean both banks)

It runs great, idles fine and gets 17-19 MPG around town.

New air filter.
New fuel filter. (65 PSI)
Cleaned MAF and tried a different one.
No obvious vacuum leaks. (Propane test)

Took it to the mechanic today. He could find no vacuum leaks but replaced the upper intake seals. Same problem.

He was extremely frustrated and said maybe the dealer can find something.

Any help or suggestions would be appreciated. It looks like I am falling into the same trap as almost everyone else with these codes.

I have not replaced the O2's because it is both sides and the truck has reasonably low miles.

What are the odds that the dealer would do any better?

Thanks

 

[locknar]

could be a coil pak, with both sides going, it could be the PCV, some of the years had issues with the PCV hose cracking.

 

[elgato]

At this point what would you expect from the dealer in performance and cost?

Thanks

 

[locknar]

At this point what would you expect from the dealer in performance and cost?

Thanks

not much, I have a very low expectation of stealers. I have seen posts of $338 for a PCV.

 

[elgato]

Here is the response from the dealer:

Hello! Ford charges $150 for a full diagnosis with check engine light concerns... If you choose to do the repair, the diagnosis charge goes towards the repair, or at worst case scenario if you want your mechanic to do the work, we can release all information gathered by our computers and technicians as well as computer and diagnosis documents, part numbers etc. Generally if you have those codes it tends to be the lower intake gaskets causing the failure. Please let me know if I can schedule an appointment for you!

Is there a definitive test for lower intake leaks? I have seen too many posts where people have replaced them only to have the same problem.

Will the $150.00 tell me anything new?

Thanks

 

[locknar]

the part that bothers me is the mileage, most of the lower intake leaks are from engines of 180,000+ mileage. Possible lower intake, not likely. Get a liquid like wd40 and spray it on the PCV hose, it is a 90' degree elbow 5/8" rubber on drivers side, it doesn;t suck but it will bubble and gurgle,(which is why it did not show up with propane) it is really common to get holes and tears.

just my 2 cents.

 

[betomonroy]

If its lean both banks it may be nothing but a very noticeable vaccum leak.
It can be a lot of different things including a bad gasket on the throttle body or a hole on the intake hose before the MAF.
BUT any vaccum leak will create a rough idle at least and will deffinetly will affect your mileage.
This lean condition can be related to (if You don't find any leak) to bad O2 sensors or "cleaned" cathalitic converters.
Check them out.

 

[elgato]

With the stock intake box and new filter the codes show up immediately. When you clear them by removing the battery cable the truck runs rough for a few seconds and throws the codes.

When I replace the stock box with a Spectre (K&N clone) attached to the end of the same stock plastic intake tube the truck starts fine and does not throw codes immediately. They usually return but after a few hundred miles.

This is really odd!

Thanks

 

[elgato]

UPDATE:
Its time for registration renewal so I dropped the truck off at the dealer on Monday. They have been diagnosing it for two days. They replaced the MAF but the problem returned 30 minutes later. They tried a second MAF. Same thing. They exhausted their normal diagnostics so they have requested assistance from Ford. The Ford engineers suspected a sticking intake valve so the last I heard they were going to pull the valve covers for more testing. If that doesnt work they are going to focus on the fuel system.
For a while they suspected the PCM and were going to update it or replace it. Ford said no.
More to come....

 

[03xlt]

I have to say, I would really check the Fuel Pump, my trucks pump began to slowly give way, what began as lost power, turned into hard starting followed by a few lean codes followed by clogged cats........

I lost the 3 second pulse initially then while driving to get the fuel pump the truck threw a few light s at me and the cleared up.. I dropped the tank and changed the pump, cleared the codes and thought I was good to go.. Until the cats went.. Burned up from the truck running lean.. Fortunately I was able have the cats warrantied (emissions equip has federal 76K warranty). Changed the upstream )2 sensors and went on my way... But yeah a head ache..

Just throwing it out there.. Could be worth the check, all it takes it a gauge attached to the schrader valve on the fuel rail...

 

[elgato]

Update:

The dealer has now had the truck for 8 days. They installed a new PCM and flashed it.
Same problem:

 

[SMTGREG]

Make sure the dealership knows about and has followed TSB 04-17-4 on diagnosing vacuum leaks. My second thought would be to check syncro/cam position sensor timing. Check the crankshaft pulley for damage or dampener slippage. Lastly check the secondary catalytic converter for blockage. I have seen the CMP timing and pulley cause similar problems.

 

[fixizin]

8(!) days! Bloody hell... can I assume FREE loaner?

 

[rum66runner]

here's my 2 cents

1. MAF can not be cleaned safely (in a manor that doesn't yield a high chance of damaging them ...[pressurized liquid coming out of a can that is being sprayed at a thin wire do the math]).
2. Dealerships are filled with yahoo yuppers that went to UTI for "formal" training and have no actual real world training until they get to the dealer (if you don't agree with that wait 10 years for the all real mechanics to retire and see who's left) they read a book and go for it.
3. Get your truck out of that place they ignored Ford went ahead and installed a new pcm after being told not to BTW they have a machine that can test your pcm instead of just putting one in and hoping for the best. You have good fuel pressure according to you atleast and they still want to dump all of their "labor" hours into the fuel system. Doesn't sound like they have even done a thing to see if it really is running lean in the first place (not hard it's called a smog test if that yeilds nothing you can run a fuel pressure or even a compression test hell you can even test your ignition coilds).
4. Listen to ford pull the valve covers check it out. If it all looks good replace your o2 sens. If you don't believe they can be bad if you live in a state like o say Missouri that requires a 10% ethonal mix into all grades of gas including the already mixed caseys gas (unless your buying race fuel). It will burn your cats fasters and foul out your o2 sensors. In just about every GM owners maunal not sure about Ford owners manuals it warns of this.

My final thought is they are intentionally screwing you sorry if that wasn't all PC