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Service Engine Codes
When I drove the motorhome last, I got a service engine code on the dash. I read the codes this morning which were PO171 and P0174, “system too lean” for both codes. For those that are more familiar with this V10 engine, does this mean I need a tuneup?  I’m wondering if our higher elevation has something to do with it as the rig has been in Florida it’s whole life.

I cleared the codes and will monitor the engine to see if it occurs again.  Just wondering if I should go ahead make an appointment for a tuneup?
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264

Re: Service Engine Codes
Reply #1
Modern cars don't need a 'tuneup' like the old days where you adjust the carb and replace the plugs, points, and rotor or whatever.  Plugs last 100k now and all of that other stuff doesn't exist. 

Did this happen before or after the new belt?  If after, I'd take it back and have them take a look.  It could be as simple as a hose that didn't get reconnected.

In any case, the codes give you an idea of what some possible problems could be, but they don't tell you exactly what's wrong.  You need someone with the technology (a shop-quality code reader) and know-how to troubleshoot. 

You have a pretty new engine.  Odds are it's something minor (I hope).   Do you know it it's out of warranty or not?  You might be beyond the 3yr/36k full coverage, but Ford should have a 5 year or so powertrain warranty. 

Rich
2003 MB

Re: Service Engine Codes
Reply #2
When I drove the motorhome last, I got a service engine code on the dash. I read the codes this morning which were PO171 and P0174, “system too lean” for both codes. For those that are more familiar with this V10 engine, does this mean I need a tuneup?  I’m wondering if our higher elevation has something to do with it as the rig has been in Florida it’s whole life.

Modern engines do not have tune-ups, there is little to do or adjust other than replacing the spark plugs at 100,000 miles.
The codes you see indicates a fuel system issue, you should definitely have it checked, running lean can damage the engine's valves and in the worse case, burn a piston.
Can't say I have seen or heard of this condition in the V10s.
Let us know what you find out.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze


Re: Service Engine Codes
Reply #4
Code P0171 indicates Bank 1 of the engine has a lean fuel mixture. P0174 indicates Bank 2 of the engine has a lean fuel mixture. Engine Bank 1 is the same side of the engine as Engine Cylinder 1. Engine Bank 2 is the opposite side of the engine.  P0171 is triggered by the engine bank 1 upstream oxygen sensor and P0174 is triggered by the engine bank 2 upstream oxygen sensor. Upstream is between the engine and the catalytic converter. Bank 1 is on the passenger side on an E450.

Common causes of concurrent P0171 and P0174 codes are vacuum leaks, mass airflow sensor (MAF), engine computer software needs to be updated, fuel system obstructions, and intake manifold gasket leaking.

Our auto began throwing P0171 codes last month, turns out is was a failed MAF. I used my OBDLink MX+ to read the code and to see the MAF output was out of spec. Cost me $60 to replace the MAF.

I would first check for cracked or damaged vacuum lines.

Charles
Harvest Hosts + Boondockers Welcome #23975
Escapees SKP #138195
2007 23.5' Twin King

Re: Service Engine Codes
Reply #5
This happened after the belt changeout and the smog test in Lancaster, a little over an hour from home. When it was getting smogged, I did notice the engine was idling rough. I probably should’ve taken it back to the mechanic at that point but I did not. The dashboard light popped up when I was about 15 minutes from home. I pulled over, shut down the engine, then restarted but the warning light remained.

I’ll make an appointment with one of our local mechanics here in Tehachapi as I want to establish a relationship with one in this area anyway. Hopefully there is a local shop well versed in the V10 engine. I’ll let ya’ll know what they find. Thanks again for your help!

Oh, and yes it’s still under the 5-year Ford powertrain warranty and have already verified with Ford that it is transferable to a new owner. I might give them a call and see about getting an extended warranty.
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264

Re: Service Engine Codes
Reply #6
Someone probably "disturbed" a vacuum hose somewhere. EVAP lines are usually checked as part of a smog check.

Charles
Harvest Hosts + Boondockers Welcome #23975
Escapees SKP #138195
2007 23.5' Twin King

Re: Service Engine Codes
Reply #7
Someone probably "disturbed" a vacuum hose somewhere. EVAP lines are usually checked as part of a smog check.

I’ll snoop around under the hood a little and see if I can find anything obvious. Thanks!

On a positive note, I’m doing a monthly generator run and so far so good.  Love having a generator!
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264

Re: Service Engine Codes
Reply #8
For our 2017, Ford suggests changing spark plugs at 60,000 miles, transmission fluid at 30,000 miles, replace rear axle fluid at 22,500 miles.  They also went back to 5W-30 oil perhaps because they were getting better mileage with 6 speed transmission.
Ross Taylor
2017 MB

Re: Service Engine Codes
Reply #9
For our 2017, Ford suggests changing spark plugs at 60,000 miles, transmission fluid at 30,000 miles, replace rear axle fluid at 22,500 miles.  They also went back to 5W-30 oil perhaps because they were getting better mileage with 6 speed transmission.

Interesting that Ford changed the spark plug change interval from 100,000 miles to 60,000. Wonder if owners of older rigs should do the same?

The axle fluid change at 22,500 can be increase significantly to 240,000 miles by using a 75W90 synthetic axle fluid.
From Ford's V10's maintenance schedule, in the owner's manual.

"Rear axle maintenance: A rear axle fluid change or level check is not required unless a leak is suspected or the assembly has been submerged in water. During long periods of trailer towing with outside temperatures above 70°F (21°C), and at
wide-open throttle for long periods above 45 mph (72 km/h), change the rear axle fluid every 22,500 mi (36,000 km) or three months, whichever comes first (rear axle is filled with non-synthetic fluid). This interval can be waived and 240,000 mi (380,000km) service interval can be used if the rear axle is filled with 75W90 synthetic gear fluid meeting Ford specification ES-PM-M2013, part number XY-75W90-QLS, or equivalent. "

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze

Re: Service Engine Codes
Reply #10
I did not know that the Ford maintenance recommendations vary so much by year.
For our 2010, the Ford Scheduled Maintenance Guide recommends automatic transmission fluid change at 60,000; spark plug change at 90,000; rear axle lubricant replacement at 100,000; and engine coolant change at 105,000.  Our LD is about 84,000 so the transmission fluid has been changed but none of the other work yet.
Link to Ford Maintenance Schedule:
https://owner.ford.com/tools/account/maintenance/maintenance-schedule.html
Paul H.
Paul
2010 MB (2011-present)                                                                                        
1994 Multiplan (1997-2010)

Re: Service Engine Codes
Reply #11
For our 2017, Ford suggests changing spark plugs at 60,000 miles, transmission fluid at 30,000 miles, replace rear axle fluid at 22,500 miles.  They also went back to 5W-30 oil perhaps because they were getting better mileage with 6 speed transmission.

Concur the 5W-30 oil for 2017 (09/16 chassis build in my case). However, my 2017 E-series owners manual shows spark plugs and rear axle fluid due at 97,500 miles. Then it states that “transmission fluid and filter (5-speed transmission only) every 60,000 miles. Consult dealer for requirements.”

How did you hear about these changes? Is this coming from Ford or your dealer?

Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264

Re: Service Engine Codes
Reply #12
I’ll snoop around under the hood a little and see if I can find anything obvious.

After snooping, I didn’t find any disconnected lines but I did notice the engine air cleaner housing may not have been seated properly. Could this be the cause of a check engine light?

By the way, that housing was very difficult to put on properly!
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264

Re: Service Engine Codes
Reply #13
One of the engine gurus can verify, expand on, or correct this (and please do for all of our learning curves!), but I think that if in a 2017 V-10 the MAF is in the same assembly as the air filter housing, and the housing is not secured correctly with the "snap band", I believe that the computer could read the wrong amount of O2 and throw a "lean mix code".

I agree that the air filter housing is a bugger to seat and connect with the band; I've done it many times, on my own and a few other LDs.

While the housing is off, I'd check for any debris and for the condition of the air filter; if it's dirty, install a new air filter! The Motorcraft replacement air filter number is FA1632 (2000-2019 V-10s).
2003 TK has a new home

Re: Service Engine Codes
Reply #14
When you say change spark plugs, I guess you are also changing the coils. Plug be cheap, coils ain't.
Our 2007 needed coils at just shy of 80,000.
Don & Dorothy
Sold our LD in June of 2023

Our boring always non-PC travel blog
Traveling Dorothy

Re: Service Engine Codes
Reply #15
One of the engine gurus can verify, expand on, or correct this (and please do for all of our learning curves!), but I think that if in a 2017 V-10 the MAF is in the same assembly as the air filter housing, and the housing is not secured correctly with the "snap band", I believe that the computer could read the wrong amount of O2 and throw a "lean mix code".

If the leak is downstream of the MAF, it could be the source of excess air, causing the lean mixture CEL.
Assuming the entire air cleaner assembly, which includes the MAF, was removed to access and change the serpentine day. It could have been reassembled incorrectly or the MAF plug could be loose, disconnected or damaged during the proceedure..
I would remove the air cleaner housing and check that the tube, that connects to the intake manifold, is fully pushed on and the hose clamps are tight. Removing the air cleaner assembly does require removing two small bolts and disconnecting the MAF or carefully laying the half housing aside.
It isn't rocket science.
2017 FORD F-450 SUPER DUTY 6.8L V10 Exhaust & Emission Parts | RockAuto

Lean mixture could also be an injector issue, the 2017 OBDII system should be sophisticated enough to detect a lean condition or misfire in an Individual cylinder.
A failing O2 sensor is another possibility. A decent hand scanner can be used to watch the O2 sensor's voltage output, observing if the normal voltage swings are present and at the right frequency.
Might be time for a trip back to the shop. I would check the air cleaner and MAF plug first.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze

Re: Service Engine Codes
Reply #16
Oh, and yes it’s still under the 5-year Ford powertrain warranty

One of the great things about a vehicle under warranty is that you can give it to someone else and let them figure things out!

Rich
2003 MB

Re: Service Engine Codes
Reply #17
Lean mixture could also be an injector issue, the 2017 OBDII system should be sophisticated enough to detect a lean condition or misfire in an Individual cylinder.
A failing O2 sensor is another possibility. A decent hand scanner can be used to watch the O2 sensor's voltage output, observing if the normal voltage swings are present and at the right frequency.
Might be time for a trip back to the shop. I would check the air cleaner and MAF plug first.

The chance that both pre-cat O2 sensors or two injectors on different cylinder banks failing at the same time is infinitesimal. Plugged-up air filter, vacuum leak, and failing MAF are the most suspect given I've never removed the entire air filter housing to know where the MAF is.

Charles


Harvest Hosts + Boondockers Welcome #23975
Escapees SKP #138195
2007 23.5' Twin King

Re: Service Engine Codes
Reply #18
When you say change spark plugs, I guess you are also changing the coils. Plug be cheap, coils ain't.
Our 2007 needed coils at just shy of 80,000.
Spark plugs are electro-mechanical devices while coils are purely electrical (except for the connections). Plugs physically wear out over time that can be predicted, coils just fail without warning and not at a predictable age. I see no reason to change coils until they fail; upon use existing coils will last for many years and the chance of failure drops as they have survived "burn-in".

Recently my SIL's 15 year old car started throwing codes and running poorly. She took it to the local dealer and they said it needed new coils and plugs at a cost of $700 to $800. My brother said forget that and instead changed the plugs and MAF sensor for $150. Problem solved.

Charles
Harvest Hosts + Boondockers Welcome #23975
Escapees SKP #138195
2007 23.5' Twin King

Re: Service Engine Codes
Reply #19
Ok, refresh my memory, what does MAF stand for?
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264

 
Re: Service Engine Codes
Reply #20
Mass Air Flow.

Charles
Harvest Hosts + Boondockers Welcome #23975
Escapees SKP #138195
2007 23.5' Twin King

Re: Service Engine Codes
Reply #21
Mass Air Flow.

It's the sensor that measures the amount of air entering the engine, critical in controlling how much fuel is injected into the cylinders to maintain the proper mixture ratio of fuel to air for good fuel economy and emissions.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze

Re: Service Engine Codes
Reply #22
Just a follow up on the service engine code issue. Drove the motorhome down our mountain and around the valley a little bit and then back up the mountain to home. I had cleared the codes earlier, and I’m happy to report that the dash warning light did not reappear, as of yet. I am hoping that by reinstalling the air filter housing correctly that it solved the problem.  I will keep monitoring in the meantime.
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264

Re: Service Engine Codes
Reply #23
Yes drive time does 'cure' some trouble codes, if the malfunction is fixed.  Gas cap seal is another one that will, as with a high number of 'misfire' errors.   RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB

Re: Service Engine Codes
Reply #24
A final follow up on the service engine codes I experienced last month.  Just returned from a trip to the coast and, after driving over 400 miles, the service engine light did not reappear.  I’m now confident that the loose air filter housing was the cause  but will keep monitoring.
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264