Ford Explorer 4 0L SOHC Rough Idle Part #3 Smoke Machine

In this video series, I will show you how I am attempting to fix a rough idle on my 1999 Ford Explorer 4.0L SOHC. I will show you how I used my inexpensive obd2 scan tool (with live data) to troubleshoot my vehicle. I used the fuel trims (long term) to help diagnosis a vacuum leak. Then I will show you how I found the vacuum leak. I tried several methods to find it, and I demonstrate a few of those methods. In this end I found the vacuum leak with a homemade smoke machine that I converted from a fog machine.
To see the videos in this mini series click the links below
Ford Explorer 4.0L SOHC Rough Idle
Part 1 Fuel Trim • Ford Explorer 4 0L SOH...
Part 2 Vacuum Leak Hunting • Ford Explorer 4 0L SOH...
Part 3 Smoke Machine • Ford Explorer 4 0L SOH...
Fog Machine Converted To Smoke Machine
Part 1 Overview • How To Use A Cheap Fog...
Part 2 Modifying • How To Use A Cheap Fog...
Ford Explorer 4.0L SOHC Upper and Lower Intake Gaskets
Part 1 • Ford Explorer 4 0L SOH...
Part 2 • Ford Explorer 4 0L Upp...

[@obxguy1]

That’s an awesome idea. I still have my fog machine that we put out every Halloween.

[@Floridays48]

Iv'e thought about doing this before and wound up making a paint can smoker, the fogger your using is latex fog, it doesn't stay warm long enough, suggestion, run your car until it's warm then hook up your fogger and the latex won't be condensing so soon I think you will see much stronger results.... good luck!

[@figibloom]

Thanks for the tip!

[@Gkitchens1]

Using a fog machine you want to use thicker fog juice (can mix your own, vegitable glycerin and water) and you really want to do it at night with a shop light so you can see it more distinctly.

[@kurtporter1323]

Cool mechanic trick...i like it !

[@lawrencetravillian8199]

Cool beans got some helpful info thank you so much

[@figibloom]

Thanks for watching!

[@KarlHamilton]

That worked really well!! Subscribed :)

[@figibloom]

Thanks for watching and subscribing!

[@MikeBlezien]

I was watching your video on this fog machine great idea. I was wondering if you noticed any problems with residue left inside the engine after running the fogging fluid through the engine or does it just dissipate and evaporate .

[@tommcdaniel4900]

Great video...thanks for sharing and being so candid in your comments about the size of this machine vs. real smoke. Did you make the real smoke machine yet? If so, how are your results? Thanks again for sharing. :)

[@TheOutlaw256]

i run SBC BUILT FOR THE STRIP.have a vacumm leak somewhere on the intake ,which is a tunnelram. I can feel gas leaking out of it between the top and bottom halves.there isn't mamny vacumm ports on my car but im hooking up our Halloween fog machine to it today. straight to the intake. thanks for this video. just saved me a lot of time replacing gaskets that might not even need it. again thanks. oh and by the way.ive been turnig wrenches for over 45 yrs building old school hotrods and custom Harleys and never thought of using this fog machine ive had in the storage building for 10 yrs..lol learn something new everyday!!lol

[@figibloom]

Well I hope you were able to find your vacuum leak. Yeah I love watching youtube I am always learning something new. I like to see how people figure out different ways to get things done. I have learned a lot of methods for finding vacuum leaks. Some of the other methods I like to find vac leaks are the water method, it is as simple as getting a bottle of water poke a small hole in the cap, and squirt down around fittings and gaskets, you will hear it suck water in and find your leak (scanner danner teaches this method, and it works great). Another one I use is done with a scan tool, and while observing fuel trims, start pinching off vac hoses (if you see the fuel trims correct themselves that is where the vac leak is, south main auto has shown this technique) Another method is done with very low pressure air hooked to the intake (1psi max), and block off throttle body (i usually use a latex glove) to seal the system. Then I use a leak detector solution, it is a blue solution that bubbles (i buy mine in the plumbing supply section of home improvement store) same stuff used to find leaks in gas pipe. With the intake pressurized spray that solution all around and where you see bubbles that is where its leaking. Oh course you can always go old school and spray brake clean, carb clean, or propane, and find the leak, but those methods can lead to things catching on fire but work great. Well I hope this info helps you out. Thanks for watching and thanks for the comment. Have a great day, and good luck on finding your vac leak.

[@nameunavailablePi]

I would delete the 1st video and rename the 2nd and third. Cicada noise is fine by me though. I love it. Thanks for the pvc idea of how to neck down the machine to a useable size. Just what I needed.

[@splizz]

We use a very simple $30 exhaust pipe adapter at the shop. We back a second vehicle up to the one we are working on, connect the adapter and it works just as good as any EVAP machine. You can make these adapters yourself. Best to use a diesel engine vehicle, or by a small bottle of pure glycerin from your local drug store and squirt a little inside the tale pipe if using a gasoline vehicle.

[@figibloom]

Huh that is very interesting concept, you should make a video on that. If you do make a video showing what you are talking about send me the link, I would like to see exactly what you are talking about. Well thanks for the info, I will have to ponder that concept for a little bit. Have a good day.

[@scooter12368]

excellent inovation

[@figibloom]

+scooter12368 Thanks I appreciate it. Have a good day.

[@chrispompano]

Doing this at night with a bright hallogen flashlight like that automotive Smoke Wizard Machine does might help find the smoke leaking and also use UV dye.....

[@byronmorris1594]

Thank you I will try that way later.

[@figibloom]

Well good luck to you, I hope everything works out for you. Thanks for watching and thanks for the comment. Have a good day.

[@mtd0766]

nice video. I've seen more smoke come out of a mouse smoking a tiny cigarette

[@fishfire_2999]

open the throttle up while you try it let air in

[@chrispompano]

Good to know..........Yes open the throttle up Wide Open to let the smoke pass into the intake better.

[@mechanicandskills7215]

But but but what happened to the FIRST one you built ? the one with the glow plug ? not work ?

[@MrSilvernblackblood]

I saw on another video using the same machine, that only the hose is held about an inch away from the output of the machine to minimize the smoke wetness. anyhow that's how I interpreted it cuz one person complained about that and that's what the guy replied, makes sense.

[@figibloom]

Thanks for the info!

[@neroj7690]

Top man,great video! im thinking of making one myself.have jeep patriot and on idle long term fuel trim is sitting around +10 plus hesitation from 1000 to 2000rpm.air leak?

[@figibloom]

Yeah they are pretty handy to have to find vacuum leaks for sure. The one I made in this video worked and I did find a few leaks. However, overall I was not to happy with it. I think the fog was a little to much moisture for this type of application (little wet) So I am in the process of making another one that will use real smoke and not fog. I have seen many versions online using nichrome wire, paint bucket, baby oil, wick, and a propane regulator to keep the pressure low. However I am going to make mine a little bit different. I got all the parts I need for it, just have not had the time to make one yet. So if you do make something I would suggest using smoke and not fog, but the fog machine did find my leak though so I cant knock it to bad. Anyway about your positive fuel trims at idle yeah it is possible a vacuum leak is causing that, but then again a lot of things could be causing positive fuel trims. If your fuel trims tend to get better at higher rpms (check fuel trims at 1500, 2000, 3000 rpm) typically if the fuel trims get better as you increase rpm you may have a vacuum leak, and if they get worse you may have a fuel delivery problem, or possible skewed sensor. Lean conditions are caused by to much air or not enough fuel. Obviously there is a lot more to it than that, but that is typically what you want to keep in mind when troubleshooting this type of problem. However, it could be anything from vacuum leaks, fuel delivery issues, skewed sensors (o2, map, maf, tp, ect, and any other sensor that contributes to fuel pulse width), or air infiltration some where, intake leaks, or exhaust leaks, or if you have a misfire in a cylinder. If you have a cylinder full of air that did not get burned up due to a misfire, that unburned air will get pushed down the exhaust and cause the o2 to output a false lean. So keep in mind could be a lot of things. Well I hope this info helps you out. Thanks for watching and thanks for the comment. Have a good day.

[@neroj7690]

+AJ “Figgy” Pierce if it had a misfire it would do it across all rpm range.changed sparks,checked coil resistance,pcv valve rattle although is a little bit oily.looked at o2 sensors.readings looks fine. anyway,thanks for extensive reply and looking towards seeing more videos on your channel.thumbs up

[@fabioaarroyo9653]

it is a lot easier to do it by using the smoke from a cigarette, I di it in about 5 min to remove the intake hose and another 30 seconds to see the smoke coming out from egr valve

[@scottyboy2400]

Try a black-light to help you spot the leaking fog.

[@figibloom]

I will try that next time. Thanks for the tip. Have a good day.

[@outsidernu]

DID you ever fixed the problem like was in the intake gasket or was it something else

[@figibloom]

I replaced intake gaskets upper and lower and it made it better, but I found other leaks at the fuel injector adaptor seals, pcv valve, egr tube seal, and crankcase vent and that is buried under everything. Really I think the trouble is its an older vehicle, and I keep finding little things wrong, but I have a few other videos you can check out in my ford explorer playlist that shows some things I have done to it. I have some of it torn apart right now, but it has just been to hot outside to mess with it, and I have been putting it off, but I will be putting it all back together soon and rechecking somethings. Well thanks for watching and thanks for the comment. Have a good day.

[@keeganrasmussen977]

I mean... This might be a better idea than spraying a bunch of shit all over it... I'm just gonna wait for a warm enough day and detail then real quick before I get into heavy cleaning before the major engine work I have coming up... Major as in price... Most of the stuff is easy stuff if you have the right tools and parts, which I also don't, so the price just double or trippled per fix.... Maybe I'll just but some tools or something... Living in the car though, so I don't really have much of anywhere to keep em.... Also, your maf side breather tube isn't properly connected and ain't leaking, but I assure you there's a fair bit of pirate air coming in through that.. enough to trip a p0171 or p0174 alone from the looks of it

[@GlynRobinson]

thank you for this video. i will never own another ford 4.0. haha

[@figibloom]

+Glyn Robinson You are welcome. Yeah this particular engine is a crazy one for sure, and can be a real pain in the butt working on it. Thanks for the comment and have a good day.

[@douglasgoldstein8990]

My 99 ranger is a 4.0 and I just passed 290k miles, running strong. Proper engine maintenance isn't for everyone.

[@aros007z]

F.o.r.d = fix or repair daily!

[@billkrause4585]

Lite up a Cuban Cigar and open a beer and enjoy the work. Thats what I do to find a vacuum leak.

[@juan64bits_]

Hello, excellent video! A little question, may be you can help me, what means this values?: At idle (LTFT +10% , STFT -4 ) At 2000 rpm (LTFT 0%, STFT 7%) At 3000 rpm (LTFT +4, STFT +4) My mileage is very bad!!

[@figibloom]

+Juan Gabriel Florez Moreno Well basically your engine computer (pcm) receives input signals from several sensors examples are map or mass air flow, o2 sensors, baro, throttle position, engine coolant temperature, and a few others. The computer interprets these signals and in turn the Pcm controls the pulse width of the fuel injectors. Basically the pcm takes the info of the sensors and determines how much time to turn on the fuel injectors. All of the sensors play a part in letting the computer know what is going on, and the computer adjusts the fuel injector pulse width accordingly. The computer wants to make the engine run at the best air to fuel ratio to support complete combustion which is known as the stoichiometric ratio. This ratio is the ratio that promotes the best ratio for emissions. Now this is not the best ratio for fuel economy (for fuel economy you want a leaner mixture) or power (for power you want a richer mixture), but the ratio the computer is trying to maintain is the best for emission purposes. One sensor that plays a huge role in letting the computer know what is going on in the exhaust pipe is the o2 sensor. This sensor usually sends a 100-900 milivolt signal to the pcm, and depending on the voltage it sees it can adjust the fuel injector pulse width. A low voltage range is telling the computer it is seeing a lean condition and a higher voltage is telling the computer it is seeing a rich condition. Now the fuel trims are letting you know what the computer is doing with the fuel (long term fuel trim and short term fuel trim) stft are immediate adjustments and ltft are done over a period of time. So if the o2 sensor is reporting a lean condition the computer will add fuel (+ fuel trims), and if the o2 sensor is reporting a rich condition the computer will take fuel away (-fuel trims). Now just telling you very basics you can see there are a lot of factors that can screw with fuel trims everything from computer inputs and computer outputs. There are several tests to do to try to narrow down what is causing your potential lean, false lean, rich, false rich problem. Basically testing sensors individually, tests to see if o2 sensor is responding to rich or lean issues (like propane enrichment or create vacuum leak). A lean condition is caused by either to much air or not enough fuel. A rich condition is caused by to much fuel or not enough air, and really this is a very simple concept to grasp. However, not as easy to figure out because it can be caused by a lot of things. Well I hope this info helps you out, but if not I would suggest looking on google for more info about fuel trim diagnosis. Also just looking at your numbers you gave me,I might guess that you have a slight vacuum leak, because the fuel trims improve under engine load, but I am just guessing. Thanks for the comment and have a good day.

[@juan64bits_]

+AJ “Figgy” Pierce thanks a lot!! I will look for a vacuum leak. may be an spray test? or going direct to a smoke machine?

[@Case_]

Given those fuel trim values, it looks more like a fuel delivery problem than a vacuum leak. With vacuum leak, the fuel trim numbers should get better as you increase rpms. Yours get worse (6 at idle, 7 at 2000 rpm, 8 at 3000 rpm), which suggests vacuum leak is not the issue. Maybe a clogged fuel filter? However, your fuel trim is still under 10 percent, so it's still considered more or less normal. Fuel trim this low shouldn't affect gas mileage much.

[@juan64bits_]

Yes, you're right. My fuel trims was getting worse since. Now I'am reading the follow values: LTFT=+18.8%, STFT=0 (open loop) IDLE LTFT=+18.0% STFT=+25%, (Transition open to close loop) IDLE LTFT=+18.0% STFT= fluctuate around 0% (Close Loop) IDLE LTFT=+16% STFT = +3% 1500 RPM LTFT=+13,3% STFT=+5% 2000 RPM So, i'm sure that something is wrong with the fuel delivery system :/ My mileage is poor on city. Now I only wish that the pump is not the problem (is one assembly without posibility of repair)

[@jrno93]

Wbat scan code did you get?

[@SweetyCHa2nel]

Hello! I have a similar problem, at idle, long-term adjustments show a rich mixture (-20%) The engine is running unevenly, trying to stall. Tell me, what kind of readings did you have at the time of the uneven work? I

[@figibloom]

My husband passed away years ago, but I hope you find someone else on here to answer your question. Thanks so much for watching his video!

[@SweetyCHa2nel]

@@figibloom I'm sorry for your loss! Thanks for the answer!

[@sara78130]

im ordeeeer one thanks

[@figibloom]

You are welcome.

[@TheRoguelement]

Hey bro your making the smoke fight hard to get past your closed throttle body blade...!!! I'm just saying

[@ricgomez1]

are you using a Halloween fog machine?

[@jrno93]

The brake booster hose is too tight can't pull it out without breaking the white plastic thing

[@vancouverman4313]

If you're going to use a smoke machine, at least play some 70's disco to go with it.

[@edwardmilewski4361]

I bought a 04 sport trac by Ford basically a explorer.. body is iij great shape but eveday sine I bought it 10 days ago I keep finding shit craftsmanship with it half the electric stuff in truck is dead now in noticed crank shaft pulley is wobbly meaning its shot now too I got 4 years to pay on this junk and I'll end up broke fixing everything wrong with it biggest problem is the pulley problem..800 to repair that or have many other issues if I drive it anymore like that....I wish I did my homework before I blew 6700 on this junk