Hello!

I might have screwed up here....up hope not.

I have a 00' 5.4 litre F150. I tried to take the MAF off the filter housing but couldn't figure it out. That 1"x2" rubber plug that looks like comes out on the side of the housing....do you take that out somehow? I couldn't get it to come out. Thot I might pull some wires apart.

Sooooo.....I tried cleaning my MAF using a Qtip and denatured alcohol without detaching it from the filter box (I had it apart but couldn't find my LPS Contact Cleaner). I might have bent one of the wires. All because I could not figure out how to get the MAF out of the air cleaner box. Lookin for the torx screws but didn't see any.....did I screw up? I read all the posts I could find, but I couldn't see where any Torx screws were on the filter housing.

Now my truck runs rough at idle. Just coming home from work at a stoplight, had it in drive with brake on. After a little while (minute or two) the idle went way low (500 rpm and lower) kept idling rough until I put it in neutral and revved it to get it back to idling right. Even if I let it idle in neitral for a while (3 or 4 minutes) it will start to idle rough. Other than that it seems to run fine. Never, ever, ever had that problem before. But...that ain't all....the story continues.

I have been looking for a 2000 Merc Mounty for my wife (V8 AWD). In looking through posts at another website about Explorers and Mounty's I came across some posts about owners having to much play with the throttle and used twist ties to take some slack out. So I checked my F150. Decided it was real loose and added a small fishing weight around the cable to take out some slack(not all of it). I gotta admit, throttle response was immediate! Sure felt like it took off a lot quicker.

I did these two tricks (MAF cleaning/goofup and slack adjuster)at the same time while also taking the battery cable off to reset my computer. It ran fine at first startup...in fact.... sounded nice, smooth and quiet I and let it idle for a while (15 minutes).

Took it out on the highway and it didn't seem to want to shift quite right at top end(3rd to OD). In fact I couldn't get it to shift at first into OD, but it finally did. But now I got this funny problem of rough idle when stopped for a while, like at a stop light, in gear. It also slows down way under normal idle when coasting rather than say just staying at an idle speed while in gear such as just cruising slowly around the neighborhood. Used to be able just to idle along without foot on throttle, now I have to keep foot on throttle or the idle goes real low and feels like it may die.

I'll take the weight off around the throttle cable out soon, maybe today, to see if that makes any difference.

Is the throttle cable linked to shifting at all? Did I mess up the MAF? Is a little bent wire causing this or is it a compound of both "tricks". Did I not let my truck idle long enough after the computer was reset? I shoulda left well enough alone!!

Please help, gotta get my truck running right again!

Dc Larson
00' F150 4x4 ExCab Lariat
5.4 Litre w/Diablo Sport Chip
WMS Velocity Tube

 

Theres a chance you bent one of the MAF wires, whcih would probley mess up the amount of air thats entering the engine. I would not be worried about the battery because if you let it drain and then let the truck run for +-10 mins you should be fine. Sometimes it takes a couple hundred miles for the computer to actually reset itself.
I really dont know other then you may have bent the MAF wire cause when i cleaned mine i noticed that those things would be quite easy to mess up.
good luck!

 

Thanks Green, but how do you get the dang thing out of the Filter housing! That rubber plug, which it seems would have to come out, doesn't want to come out entirely. I don't get it!

 

im not 100% sure that the bent/broken MAF wire is your problem but the bad idle could have somehting to do with wrong amount of ait intake.
i dont know how to get the MAF out. Someone that knows how will soon post and give you some insight as to whats wrong and what to do

 

It may have possibly partially unplugged on you, which would cause the same symptom as a broken sensor wire. As long as the wires inside the MAF are still connected on both sides, it should be okay? On my MAF, the wires are slightly bent from numerous cleanings, and it has had no effect on it really. On my 98 model housing, there are little clips around the of the outside of the plate the MAF is bolted to. I believe it's two, or maybe three(been awhile). Once you undo these clips on the plate, you maneuver the MAF around so you can undo the plug. I'd recommend trying taking it apart again, just to make sure it's not unplugged. My truck did the same thing when I forgot to plug it in after cleaning once.,,,,98

 

Have you driven it over 48mph since disconnecting the battery ?
This has to do with full closed loop opertion fo the MAFS, IAT, EGR and O2 sensors. If you screwed the pooch on putting the MAFS back in ( disco'd ) then a CEL would have been set, and you should have a code waiting.

When you put it back together, did you check that all hoses ( crank case hose specifically ) were put back on correct, or if you did not take them off, did you check them to see if one worked loose ( talking about the 2 up by the throttle body under the cover ), and that the bulb sensor for the IAT is seated correctly ?

Rough idle and dying at idle can be a few things, but checking to make sure the system is colsed, and that no additional air is making it into the engine to screw up the closed loop operations is the first thing to check considering that you just had it apart.

All areas to check : the entire intake from the filter / MAFS connection up to the throttle body, including the hoses up by the T/B.
Vac lines ( there is a whole mess of them, and considering that you were doing something to the throttle cable, you could have mistakenly knocked one loose or the EGR hoses ( but the EGR hoses off, should cause a CEL after the first time over 48 mph )

If the intake system sees additional air getting into the system that is un-mettered this can cause rough idle problems without a CEL straight away.

long story short, check the intake to make sure it is closed up 100% and that all vac lines are closed.

If you have a VAC gauge, and can splice it into the system this might help. Should have about 21-22 in/hg at idle. The place I spliced mine in is at the firewall on the pass side, kind of where the PCM goes throught the firewall.

Good luck in tracing all the hoses and lines, it could take a while, and a few beers

Others have said that thier truck runs rough after resetting the PCM for a little bit, but did not say how long it was ( the full 200 mile retrain, less, more ??? got me...my 5.4 never does that )

Let us know what happens

 

Hey!!!!.....Hey ...Hey.....Hey!!!

I might have found the problem....I went outside at lunchtime, man it's really snowin.

I went out and looked and just noticed the lower of the two hoses that hook into the air tube just before the throttle body, was disconnected. Thats gotta be it....right? I'll drive it later and find out. Should I disconnect my battery cable here at work before I go home? I can start it and let it idle a while before I take off for home.

I will still be wondering how to get at the MAF. The "plug" I'm talking about is on the bottem of the air filter housing so I couldn't really see any screws. If I buy the electrical parts cleaner (LPS instant contact cleaner) do I need to take it completely apart? Or can I just look at it thru the filter housing and spray from there?

 

Just drive it home and disco the battery there. It might still run rough going home as the adaptive programming is still learning, but starting the process with the additional air getting into the system, you should just start over.

If you can deal with it, you should wait for the roads to be clear, and then start the retrain.

The reason I say this, is after the disconnect of the bettery, besides the letting it idle, then next thing before shutting it off, you should go out and drive it like you mean it, on and off highway. There is more detail in the chip forum on this, but I always take it out on a retrain and stand on it, running WOT through to at least 3rd gear, then constant 70 mph, then off the highway on to a surface street for some 35 to 45 mph driving.

A few stops in there is a good thing, and run it up a little when taking off from the light. This may seem old school for the train, but I have always had good luck with doing it that way.

Take it with a grain of salt, and check around on the best way to retrain the adaptive learning process.

 

[edit : screw that last post I put here, it made $h!t for sense ]

Here is the pics of my K&N FIPK install. I had to go look for the instructions, and low and be hold I still had them.

Once you take apart the filter housing as of you are going to change he filter, under the filter housing where the housing is snaped into place with 2 locators, there is a connector for the MAFS. Un do the clip there, and the wiring will be free from the truck itself ( wiring harness pigtail going through the gromet inthe the air cleaner housing. ) then look at these pics:

https://www.f150online.com/galleries...2028-48036.jpg

https://www.f150online.com/galleries...2028-48035.jpg

https://www.f150online.com/galleries...2028-48037.jpg

Don't take the plate off in the last picture, that is just to show you what it would look like.

Let me know if this answers your questions on getting the MAFS out of the air filter housing.