Ford F-150 P0171 P0174 Trouble Codes - vacuum leak (water test)

How to determine the cause of a lean condition on a Ford 5.4 engine.
How to locate a vacuum leak without a smoke machine.
For more information on this topic, I have written a “field manual” called Engine Performance Diagnostics which is available at www.scannerdanner.com as an eBook or paper book.
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On ScannerDanner Premium I will bring you right into my classroom at Rosedale Technical College. You will find page for page lectures taken right from my book as well as exclusive classroom type case studies. What is so special about these classroom case studies? I pull live problem vehicles directly into my classroom and we troubleshoot them in real time, using and applying the theory and testing procedures we learn during the classroom lectures. There is no better on-line training of how to troubleshoot automotive electrical and electronics systems anywhere!
Disclaimer:
Due to factors beyond the control of ScannerDanner LLC, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. ScannerDanner LLC assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. ScannerDanner LLC recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of ScannerDanner LLC, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not ScannerDanner LLC.

[@brakedd]

You hit the nail on the head in the beginning, brother. Those are the best videos, where we get to see/hear your thought process and direction as more evidence presents itself.

[@georgebonney90]

I'm re-watching your chapter1 playlist,its great to see your thought process,the way u explain when ur in the field u can really tell ur a teacher and I really appreciate it

[@ScannerDanner]

Thanks so much!

[@freddy2064]

Mr. Danner, although I have watched this video in the past....I still stick around to watch it a second time. Your content is awsome, thank you for sharing brother.

[@perverso12345]

live videos are fun .we get the chance to grab popcorn while you are talking ....

[@michaelherbert8213]

Love the"real time" unedited videos.

[@guayaco-dm3vu]

Almost didn't think it was a vacuum leak cause fuel trim didn't come down more.... Once again Paul,You are the man..

[@robhertfernanda]

I love the fact you said you are putting your seat belt on, thanks for sharing the knowledge, I'll be subscribing to your channel as soon as I get a chance

[@toyotatechMDT]

Great video Paul. Welcome home! Appreciate all the live videos. Thanks.

[@jonascourtney5999]

Thank God you are strong, wise and healthy. I pray He will keep you this way for the longest time and you will enjoy life to the fullest. Thank you for your video.

[@ScannerDanner]

Thanks James! That really meant a lot to me.

[@moneygrip4464]

Sometimes I wonder if god has favorites...

[@pamelavance648]

​@moneygrip4464 nah he just returns the goodness.. anddd maybe favorites 😊 make it a good deed day

[@movingupautodiagnostics8645]

I can see how blessed you are and how you enjoy your work. Also I can testify that you're blessed because you bless others. Thanks for your hard work Paul, shalom brother.

[@ScannerDanner]

Thank you my brother. And shalom to you too!

[@brenda54097]

Moving Up Diy

[@brenda54097]

Moving Up Diy

[@billmill50]

DTC GM code P01639 Thanks again

[@1geromette]

Thank you ScannerDanner! What a great video and the fact that you shared this info will warrant you a special seat in Heaven!

[@ghost37666]

Love your honesty, clarity and of course your openness.

[@ScannerDanner]

I appreciate that!

[@josealers67]

Thanks Mr Danner for sharing your awesome videos and your expertise. ..

[@SLICKKID74]

Great video. Visual inspection is an important part of proper diagnostics. Just had one of these 5.4 in an expedition last week with lean codes. Drove me nuts!!! Found 3 obvious vacuum leaks and ended up sealing air filter housing.

[@garyfunderburg9081]

K kI

[@Inkd_watkins]

This is a great video Paul. I believe too, that I am blessed to do, what I do. I too love what I do. The camera picked up the hissing of the water. I heard it. Keep it up Paul. I will always watch and wait for what's next.

[@JuanOrtiz-mo8be]

Great video You work your magic on that IAC and the guys reaction must have been like Wow this guy is good.

[@shopyard87]

You're a hard working man, great job.

[@israelzunigamascorro9300]

Excellent videos God bless you and your family too.

[@dreamer2355]

These are your best video's as we can connect with you on a more personal level :)

[@islamicwaylive]

Love this video my man. I got to figure out where my leak is at. My car is reading p0171, 174 and p0301 twice after I replaced coil number 1 already.

[@trentallman984]

Mine was just that boot working out of the socket, I had just put on an alternator so I had dislodged it in moving it aside. Thanks for the video, that is a great trick to find a leak.

[@sanpatino4678]

your videos are very helpful thank you. MR, DANNER

[@charlesgreensr9610]

Your video on vacuum leaks was a big help to me thanks God bless

[@DRmechanic1]

Thanks for the videos I did a thank you video for helping me fix my 98 Ford E350 5.4 with trouble codes P0171 and P0174.

[@VolvoGonzo]

I got the same two codes popping up on my 98 f150. What ended up being the issue? Mass air flow sensor? Throttle position sensor?

[@tomduncan1970]

Awesome...... I am hooked on your videos. Thank You for sharing your knowledge.

[@andrewp3089]

Hi, love your videos. Thanks for shearing your knowledge and experience.

[@ozzstars_cars]

I just released a step by step video on replacing the intake manifold gaskets on my C4 Corvette LT1. Sometimes people don't realize it's not just oil leaking out but ALSO causing a vacuum leak, causing a poor running engine. I like how you used water to check for the vacuum leak instead of carb cleaner which can be dangerous. Thanks for another cool vid Paul and welcome back home to all the ice and snow - Glen

[@campen777]

Your videos are like seat belts to me , uv saved my bacon so many times , so just keep doing both . ... I love ur thought proses it shows how and and why you change direction , and what realy comes across so well is your enthusiasm which for me is a pleasure to Wach .. I started in 1970 and like you I love my job . So just keep on doing what you doing ... On another note have you thought about contacting a local collage with student learning the film trade , they mite be interested in being your film crew for the day ? .

[@enriquev8832]

Great video. Thank you! I just started to learn what numbers mean on a scanner.

[@georgedawsonjr450]

Hey Paul I was talking with some others here in my town in az. We were thinking why don't you make a video that goes more into how you desire whitch way your going and how you come to the conclusion to test the components. It would give more insight to why you chose the right and what brought you to that discussion. Also on your book why you don't put a practice test in it like your classroom test. Then it would help us to know where we are week at and what to study a little harder on. And kind of a test yourself kind of quiz. Thanks for everything its really made a big change on how I now look at things. Its brought way more to my table. Thank you keep it coming. Transmission seems to be a big testing problem for us now. Not much out there on them.

[@MaicSalazarDiagnostics]

Awesome video Paul! As always with you!!

[@younismark]

great one, its not easy what you did show if you do no tunderstand what knowladge comes in diagnosing. will thanks and keep it up.

[@theearonyourcorn]

Thanks for the video man! I'm planning on doing a water test for the same code and you laid it out pretty clearly, especially showing us what the sound is to listen for. Also, if Chekov's gun were a coke bottle lol... I love that we happen to see the tool you're going to use to diagnose the problem in the first few moments of you walking into the shop.

[@ScannerDanner]

Do we?? Haha that's awesome! Thanks man

[@jamesl197999]

Great video. Keep up the good work.

[@dell05121979]

Thank you Sir for sharing your knowledge

[@genehensley767]

We appreciate you letting us in your world

[@1keykneedeep]

Awesome job. That was a nice trick.

[@inesdelgado8506]

Thank you for sharing your knowledge so cool how easy you diagnose cars and sher with us.....

[@dondangerous4553]

Expensive bottle of water (depending on the diagnostic charge), LOL! Good vid to show you don't always need high tech tools to diagnose problems. Thanks for sharing and keep up the good work.

[@martincaldera386]

Have other 2 OBDI cars, as there is too few info on them, but I am reading your book with a lot of faith. I only have a Snap On MT2500 scanner and I try to apply your courses. As you quote: " I enjoy what I am doing on these cars".

[@stevehvac1]

very good mechanic scanner .need more of you working to fix issues that are hard to figure out due to lack of knowledge.

[@ScannerDanner]

+lee steven (freedomseeker) thank you!

[@everyhome9936]

issues not fixed, just a quick "diagnosis".....my mom used to come out to the garage when I was in high school and diagnose everything; her solution was something is sticking and needs WD40 lol

[@user-ju3od5gy5q]

Just found your channel. Have spent probably 25 hrs (off and on) over past week looking for the right info concerning PO171 code (and i suspect older code never cleared PO442). Too many shops around here either up charging and or not trained personnel properly to diagnose correctly. You are also helping other families save $$ so they can also occasionally all go out for dinner. Will be referencing your videos in the future.

[@vicenterangel6655]

muy buen video mr Paul de los mejores theacher en el mundo Those are the best videos and gread to see you videos thanks Paul Danner and god bless

[@alexvega4068]

Great videos brother keep up the good work

[@robfarnam938]

Great video helped me a lot thanks keep it up buddy

[@smartchishaya1670]

I like what you said "I am blessed to be able to this".it is the will of god.well done

[@PistonShack]

Thanks Paul! God blessing.

[@jerryjamify]

thanks for a great video.

[@saladsnake7911]

I love these videos.

[@joseluiszapote2634]

Nice video ,saludos desde Ashburn Ga

[@JacobDayneko]

Nicely done Paul. Love the walkthrough process on how you approach diagnosis. I"m learning a ton. Do you think there are going to be more specialty diagnosis only techs out there in the future? how do you come up with a price you charge your customers?

[@Turbotomass]

hes right. way under paid and appreciated industry.

[@billybobhankleman6028]

Excellent videos sir... I learned a lot from them and Thank you for them. I tried your techniques and everything points to a vacuum leak but when I go search for the vacuum leak via a smoke machine and water test but there are no apparent leaks anywhere. Driving me crazy

[@jesusmalagon4336]

Thanks Paul

[@richardmedina9279]

I have the same codes P0171 n P0174 going to try the water test thanks

[@paulfiebke3909]

Wish you wood have did a smoke test on the truck, keep up the good work

[@stevenpo1963]

We used Carb cleaner in old day my great Uncle used water I forgot about that thank for great memories.

[@travyb1401]

Hey Paul loving the new video. Im just curious did u ever find out what the issue was with the Sunfire in Panama? Was it a bad engine?

[@martincaldera386]

Appreciated a lot to have seen this vid. I can´t wait to search vaccum leaks on my old 94 3.1 V6 MPFI Cutlass Ciera. It gets mad with high rpms, I´m suspecting of vaccum leak, as I don´t have smoke machine it would be handy this water test, thanks a lot respected Mr. Danner.

[@ScannerDanner]

High rpm driveability issues are never from vacuum leaks. Ignition or injector problems most likely. Especially for that year and model

[@automechanicthefox8732]

He is the best

[@mosesdog2]

Great video, great concepts. Did you Pete tell you if there was a drivability complaint? I imagine with those trims. Also, could low baro readings ever cause hesitation, or a better way to put it is it a large enough input into the PCM to cause drivability issues?

[@jose6788]

Haha Pete does not like the camera very much. Love the unedited videos Paul!

[@geojor]

thanks for sharing...

[@mikecont9742]

Great video. .

[@SRT92]

very informative...this video has answered alot of questions to my issues with my 98 4.6, I have those same codes. lean on both sides and your diagnostics where amazing accrate!! intake leaks on both sides of the intake, just like what the computer stated!!!! I'm not a mechanic, but hey I just learned something new by watching this video. I think this will solve my bad idle issue. Looking more into getting intake gaskets changed.

[@pipelineoperator8890]

check pcv valve first

[@SRT92]

+Chris Drews oh no I had that replaced a long time ago. I just got rid of it just recently, I believe that truck had timing issues. I now have a 2003 f150 stx 5.4. it's pretty awesome so far, a lot more power then the 4.6 although I have already pointed out some common issues already with this truck. Other then that, it runs super smooth, and I'm highly satisfied with it. I will post vids of it soon.

[@SRT92]

+Chris Drews I got luck too I was shocked the heater and ac was still working. it has 210,000 miles, and feels like it only has 50k miles. literally.

[@GlynRobinson]

thanks for the video. you know your stuff.

[@ScannerDanner]

+Glyn Robinson thanks man!

[@Yellowshaker1]

Great video as always, Paul. What camera do you use that I have seen mounted on your head?

[@SS-U23]

Great job just as usual. You got an awesome understanding of how STFT and LTFT are calculated in relation to an engine performance condition. I really impressed by your approach. Man, you are an expert. By the way, can a mechanic be paid for troubleshooting an engine performance issue? If they can be paid for that, how can I know how much to charge a customer for performing such a task? I have used alldata to charge for labor but not to charge for diagnostics or troubleshooting. Thank you and God bless you.

[@ScannerDanner]

Hey, it's you again :-) Absolutely! Keep watching my friend. I will teach you how to charge for diagnostic time. For me it is a minimum 1 hour okay from the customer. Making them aware this first hour is a flat fee. Meaning if it takes me 5 minutes or 60 minutes, it is the same charge.

[@boobizzy4173]

Thanks brother!!!

[@upallnight888]

We are the one that are bless that you are willing to share your knowledge and make these videos for us to see. I belong to several car forums and help other owners solve their car problems. Sometime I will direct them to one of your KZbin video if it is relevant. A person that enjoys what he do doesn't have to go to work like everyone else.

[@ScannerDannerPremium]

agree my friend, thank you for helping make my work, not work at all

[@perverso12345]

keep up tha good work ......

[@DriveShaftDrew]

good vid keep them comeing

[@malisa696]

great video mister Paul. Please upload the troubleshoot of the diesel truck you mentioned and if you can start some diesel troubleshooting in your video it will be a good new step for everybody..specially in Europe. Thanks...... p.s. AC/DC rocks at Pit's :D

[@danbooher5780]

Yes ! Thank You !

[@felixgange1715]

Good job 👍🏽👍🏽👍🏽

[@joshmedlin976]

Thanks for all your videos! I'm currently a student in a high school automotive class, and your videos have helped me tremendously. I've learned a lot from these videos.They also have inspired me to continue to tech school, and on what i want to pursue as a career. Thanks a lot man.I hope to purchase your e book soon.

[@ScannerDannerPremium]

Awesome man! You should come to my school. Would you like to talk to one of our admissions reps?

[@joshmedlin976]

ScannerDanner Premium yeah. id be more than willing to talk a rep. that'd be awesome. thanks!

[@ScannerDannerPremium]

Joshua Email me through my website. I'll need your contact information. Thanks! Don't post that info here

[@benjamintimmins1656]

Hey I used water to find my p0171 lean bank 1 code It was my intake manifold gaskets...gonna be changing them out tomorrow...I used starting fluid. Then water like I seen you do...

[@SteveRobReviews]

Awesome 👍

[@Wildcat5181]

It appears to have a new injector, and you have to lift the fuel rail to replace even one, so the leak could be multiple broken injector seal contacts from lifting the fuel rail. Even a very small piece of particulate matter introduced during the movement of dirty parts can prevent an injector o-ring from sealing. I prefer to use Berryman's Carb and Choke Cleaner with a capillary tube for pinpoint checking but there are those who are afraid of a potential fire, so it is a matter of preference.

[@everyhome9936]

EXACTLY what I was thinking when I saw that new injector. Not very precise to slosh water / liquid all over the top of the engine....is it multiple injectors not seated or bad seals.....or is it really an intake gasket bad in multiple areas. Would be easier to pinpoint with a shot of carb cleaner through the tube

[@mindiseverything5036]

Is there a scanner that is less price that you would recommend for new techs that can perform close to what this can ?

[@berniceperry8898]

I changed my intake gaskets and injector o rings on my 01 crown vic lx and when i was done it ran excellent for a couple mins then it idled down a little more and sounded like it had a slight miss, when I went to drive it it was sputtering and super sluggish I had to baby the throttle.. Any help would be appreciated...?????

[@jaimesustaita285]

Ok, thk-u paul.

[@Poochie43124312]

" Lean condition ,Where do we start? " I'd going back inside where it s warm.

[@windycityshine]

I have a 2017 colorado v6 with engine codes p0171, p2096, p015b My fuel trims stft 29, Ltft 39 when I give it gas they stay the same or go higher, Mechanic changed the spark plugs, MAF, 02 sensor bank 1 sensor 1, and nothing changed. Did a smoke test but no leaks. Any idea what direction to go now?

[@philh9238]

sportin the aviators!

[@IamReadyToRock]

Nice

[@clutch5sp989]

The rubber stopper where the MAF sensor wires go into the intake tube can come loose and trick a guy. I was at wits end knowing there was a vac leak and not being able to find it. The rubber stopper dangling there underneath the air filter tube lets air in past the MAF sensor and will throw P0171 & P0174 codes. Cleaned the parts & connections all up and short fuel trims finally swung negative settling the long terms to about 3.7 each over a drive cycle. Ref...2001 F150 5.4L

[@everardocamacho5063]

Hi scanner i got a2002 jetta 2.0 with acode po302 misfire, i done everything so far changed plugs, wires, injector, maf sensor, coil pack,check compression, check for vaccum leaks, ect, and stil Runs rough, i hook up the scanner to check alldata monitors , and noticed the upstream o2 sensor was not oscillating i disconect the sensor and now is running fine, you think the sensor was the problem all this time ,please let me know if it is the sensor i will replace it thank you paul , sd ca

[@dzorba1]

will low compression in two cylinders adjacent to each other cause lean codes

[@primetimemidwest1543]

Hey Dan I got 97 f150 runs rough code p0174, p0500 and p1405 I check for vac. Leak was none I found but when driving it vibrates real vibrates real bad

[@erickvqz77]

that was kinda. Quick.and fun but I have a question and hope you answer and if you don't I understand. On natural gas vehicles. I see that a lot. It's because of the different. Fuel

[@JPsLawn]

got the same code in my 03 2.3 ranger got steady fuel pressure at 65 with truck running..and vacuum is 20 steady runs alittle rough at idle only and runs fine or seems to run fine under load..new plugs wires and coil pack....the stupid plug in front of the intake manifold popped out so i jb welded it back in got rid of the other codes but cant get rid of this code

[@JesusSanchez-ee7re]

hey man, where are you located, I want to take my 2000 Lexus es300, I have problems with the o2 sensor, thanks

[@chrisvill54]

I must be doing something wrong because I can never find vacuum leaks with water. Does the vacuum leak have to be past the throttle body? Because I pulled a hose before the throttle body to create a leak, to see if spraying water around it would make a difference and it did not.

[@gsowe01]

could you have shown fuel trim numbers at the same time whilst doing the water test ? they would be changing at the same time I imagine

[@victorbeltran3075]

Thanks to Jahovah God for your videos and it is really a bless I really like it when you put it that way as a bless let Jahovah countinue to bless you man thanks

[@ScannerDanner]

thank you victor!

[@williamtanner8222]

Good video...though my boss doesn't like the water test lol had a jaguar that had a vacuum leak, our smoke machine was broken so I did a water test. He states that you can hydro lock an engine by doing that. I tend to think with a small vacuum leak issue, that's not gonna happen. Also, on hondas with idle problems. First step, check coolant level, if that's okay, go directly to iac. 99% of the time, that's the issue.

[@tasmaniandevil7610]

I have a 2000 f150 I removed the plenum and checked vacuum lines lots of dry. Rot I replaced everything questionable and a bend with a hole which is my Diagnosis put new gasket and not a code now but the 90 tied in the back of the plenum 4.2 v6

[@willswork510]

Subscribed

[@ScannerDanner]

Welcome!

[@alonsoautodiagnostico]

I hace the same problem un a 2007 toyota fj cruiser, present the same trouble code but the problem was un the fuel pump, this lost presure and the aire fuel mix is lean

[@alonsoautodiagnostico]

Sorry for my english, prefiero el español saludos desde costa rica