P0171 & P0174 and Service Engine Soon Light

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Thanks Drae. Added temp sensor to the list. Great ideas for marking and remembering where things go.
 

texasscot

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Before I spent that kind of $$$, I would check/replace any/all rotted vacuum hose, hose assemblies, PCV & hose & elbows that look rotted or feel spongy. Does not cost near the gasket replacement but will need to be performed especially if nothing has been done during that 154k miles. I replaced most of mine for under $200 and a little grime on my hands (use Nitrile gloves). Go to www.rockauto.com
I do not know the current discount code but someone else may chime in. There is a vacuum assy behind the battery also. Heat and age are terrible on these vacuum lines/hoses.
220249584198346788
Rockauto code valid until end of year I believe.
 
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Getting ready to start this job today. Thankfully the garage has warmed up to a toasty 42 degrees. LOL.
Based on forum posts, it doesn’t seem super common for injectors to fail, but it does happen.
Nobody’s mentioned it yet, so I thought I’d ask. Should I replace the injectors while I’m there? Overkill?
 

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The injectors should be fine. If anything, I'd just run some injector cleaner through the fuel tank once in a while. Remember to lube the injector O-rings before re-assembly, so they slide back in their homes without binding up or tearing. Close the garage door and put one of those portable heaters in there !






.
 
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Started on this project today. It's going pretty well except for one of the nipples broke off the EGR pressure feedback sensor while removing the hose. The plastic is brittle and crumbles easily. Ordered new Motorcraft sensor. However, more importantly... I cannot remove the coil from cylinder #2. I believe the brass nutsert is spinning in the plastic of the manifold. The bolt turns, but will not loosen. It also has that bumpy feel as it turns. All others were removed with no issues.
Anyone have any suggestions as to how to get the coil bolt out?
Since it's the only one, maybe just remove the manifold with the COP in place?
Thanks
 
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Looking online for a Motorcraft manifold. So far can't find one. Tried Amazon, Ford Parts Giant, Rock Auto.
 

texasscot

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Looking online for a Motorcraft manifold. So far can't find one. Tried Amazon, Ford Parts Giant, Rock Auto.
You might not like to find one lol…
I looked at only a couple of random Ford OEM places and they were similar. Maybe others know better places.
PS. Don’t tell anyone but I used a Dorman several years ago and it’s still ok. This is not an endorsement!
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I found a new Motorcraft manifold at a local dealer! $255.01 out the door! So thankful!
Inspecting with my novice eyes, the seals appear to be intact. No obvious signs of leaking. Hoping the plugs look normal when I take them out tomorrow.
So far it's not too difficult. It's meticulous, but it's doable. Take your time, be present.
Here's a few photos for interest. Anything look out of the ordinary? Any signs the valve cover gaskets are leaking?

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IMG_0181.JPEG

IMG_0186.JPEG
 

texasscot

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I found a new Motorcraft manifold at a local dealer! $255.01 out the door! So thankful!
Inspecting with my novice eyes, the seals appear to be intact. No obvious signs of leaking. Hoping the plugs look normal when I take them out tomorrow.
So far it's not too difficult. It's meticulous, but it's doable. Take your time, be present.
Here's a few photos for interest. Anything look out of the ordinary? Any signs the valve cover gaskets are leaking?
That is really great news! I have no idea why these prices should be so different. Did the Motorcraft manifold come with the big insulating “box” under it?
 
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Yes, insulating box present. The parts guy said Ford was going to release 8 of them in January. 8 for the whole nation!
 
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Could someone help me confirm the torque specs for the throttle body assembly and intake manifold? I have found the following online:
Throttle body assembly = 7 ft lbs
Intake manifold, 1st = 85 in lbs, 2nd = 18 ft lbs
Thanks!
 
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Finished. No more SES light or P0170 and P0174 codes. Runs great, but there is quite a bit of steam coming out the tail pipe. I'm hoping that it's from coolant that found it's way into the cylinders when I removed the intake manifold. I'll drive it around and check it tomorrow. Goes without saying that I really do not want to do this again.

All in all the job took me about 16 or so working hours to replace:
Intake manifold
Intake manifold gaskets
Injector O-rings
Spark plugs
Coils + boots
Thermostat + gasket
EGR Pressure feedback sensor (DPFE)
Cylinder head temp sensor
Battery

Cleaned throttle body and adapter.

I could never tackle a job like this without the support of this forum. Thanks to y'all for your assistance.
Happy New Year!
 
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whtbronco

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Awesome news. Congrats and well done.

So satisfying to complete a job like this for a lot of us and save a ton of money.
 

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So I just got the same codes on my 2004 Eddie Bauer 5.4 4wd that has 225,000 on it. We got the p0128 code and the p0171 code a few weeks ago and my husband changed out the thermostat and the check engine light didn't go out so I had it cleared. It came back on today and I had it scanned again and it gave the p0171 and p0174 codes today. It is running just fine, just has the check engine light on. I read through the stuff above and I am wondering what are the simplest things to start with to try. My husband is going to be unavailable to work on it for the next two weeks so I have to drive it every day. Any ideas?
 

texasscot

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So I just got the same codes on my 2004 Eddie Bauer 5.4 4wd that has 225,000 on it. We got the p0128 code and the p0171 code a few weeks ago and my husband changed out the thermostat and the check engine light didn't go out so I had it cleared. It came back on today and I had it scanned again and it gave the p0171 and p0174 codes today. It is running just fine, just has the check engine light on. I read through the stuff above and I am wondering what are the simplest things to start with to try. My husband is going to be unavailable to work on it for the next two weeks so I have to drive it every day. Any ideas?
You have too much air or too little fuel getting into the engine. Look for easy things first. Vacuum leaks in hoses particularly at rear of engine. It helps to take off the plastic cover so you can inspect the many hoses. The hose to the brake booster is particularly prone to deterioration. Check PCV valve is snug on passenger side valve cover. Look online at methods for vac leak detection on a running engine. check for splits in air duct after the MAF sensor. if the fuel filter hasn’t ever been changed, maybe change that.
Others on here are far more knowledgeable than I but these are some quick tests to be getting on with. Others will jump in I’m sure (and correct me where I’m off base lol).
Running a lean condition engine es no bueno, as it runs hot and can mess up your pistons and cat.
 
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