P0171 & P0174 and Service Engine Soon Light

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Kenerator

Kenerator

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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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Kenerator

Kenerator

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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.
 

alcgraham

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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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