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2007 Ford F-150 Question: code p0172.

 

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rasco 1980, 5.4L V8, Glennville, GA, November 16, 2013, 15:34
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how to fix code p0172 on 2007 f150 with 5.4 v8

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  • Answer #1

    cardocIII from Gillespie's Auto Service, November 16, 2013, 16:07
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    The code is for system too rich, bank #1. The first thing to check is the freeze frame data so that you get to see under what conditions the code set, and while doing that look at the fuel trims to see if this is just one bank that has an issue, or if both banks are out of control but only one of them bad enough to generate a code. The testing from there will include all of the basics, which include fuel pressure, the baro pid calculation in scan data, and monitor the engine load calculation to gage if the MAF is reporting correctly, and if the engine is breathing correctly.

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    ProfessorG, November 16, 2013, 16:19
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    I hate changing the plugs on those.

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    cardocIII, November 16, 2013, 16:37
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    Yea, done a bunch of them. Techs in the iATN shared some tips and one is surprising how well it works. Start by following Fords TSB about decarboning, and then breaking the plugs loose 1/4 turn and then put a tablespoon of top engine cleaner in each of the plug holes to soak overnight. Then comes the eye opener, rattle them out with the 3/8" impact! If the plug is going to break, there is nothing anyone can do about it. I've got eight trucks out of the last ten that all of the plugs came out using the routine without breaking. The other two I only had to deal with two plugs on one of them, and one plug on the other.

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    ProfessorG, November 16, 2013, 17:00
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    Have learned the similar technique , I use bolt blaster or another brand I can't remember the name right now. The same results letting sit overnight & turn my impact way down. The problem I have is when they break. No patients for me in a fast paced one tech hole in the wall, (it feels like anyway). I'm my own problem with those.

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    cardocIII, November 16, 2013, 17:31
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    LOL, know what you mean there. One man shop here, only have the wife to help with the paperwork. When I take one of these on, I let the owners know upfront that they can be a real ,um real, ah, well you know.

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  • Answer #2

    pushrod November 16, 2013, 16:18
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    Do you understand what answer 1 posted? Also are you equiped to perform a full scan test?

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    ProfessorG, November 16, 2013, 16:23
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    Yeah but I'm sure the patient doesn't.

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    pushrod, November 16, 2013, 17:42
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    Pitiful.

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  • Answer #3

    Lowcountry_shawn November 16, 2013, 17:15
     Technician

    system too rich bank 1 could be a vacuum leak but not sure

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    ProfessorG, November 16, 2013, 17:23
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    A vacuum leak would be LEAN.

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  • Medium-star Best Answer
    bmdouble November 16, 2013, 19:41
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    Have had plenty of failed injectors,as in stuck open and dripping or bleeding down when vehicle is turned off thus filling the cylinder with fuel and tripping a rich dtc. A simple way to check is to unbolt the fuel rail,spray the tops of the injectors with wd-40 and wiglle them and raise the fuel rail with the injectors still attached to it and shine a light under the injectors. I've found lots of stuck open injectors on these engines! just a thought.

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