This is a somewhat common problem, especially if you are running an oil charged (like K&N) filter. You probably need to clean your throttle body and throttle plate. I run a K&N filter and as part of my PM, I clean my TB every time I change the oil. Try This:
*Remove the intake duct work.
*Disconnect the MAF sensor connector.
*Remove the Crankcase gas recirculation line.
*Remove the Breather assembly.
*Have an assistant turn the key to the on (do not start) position and depress the accelerator fully and hold. This will hold the throttle plate open during the cleaning process. It will make a humming sound - that is normal.
*Using throttle body cleaner and several lint free rags, clean the throat of the throttle body and both sides of the throttle plate.
*Have your assistant (which could be a stick between the drivers seat and the accelerator pedal) release the accelerator and turn off the ignition switch.
*Allow the throttle body cleaner to evaporate (10 minutes) while reassembling the intake and related components.
*Start the engine and allow it to warm to operating temperature.
*Turn engine off and clear your DTC’s.

Hope this helps.

 

Thank you so much for the great details!! I love this site and all the members who make it what it is!!
I did take it to a buddy and it spit out 4 codes
P0121, P2104, P2111, P2112
Apparently they are all related to the Throttle Positioning Sensor.
Will your advice still help with these or is a throttle body with new sensor possibly needed?
Thanks again

 

P0121 is a tps circuit malfunction code.
This does not necessarily mean that the actual sensor is bad.

P2104 is a TAC (throttle Actuator Control) forced idle code.
This is probably the culprit - if the throttle plate sticks (even for a milisecond) - it will set this code.

P2111 is a Throttle actuator control system code The ECM is telling that there has been a malfunction the the throttle system somewhere.

P2112 sets when there has been a throttle actuator control system range/performance problem.

In my opinion. The tps malfunction code is probably a result of the TAC system problems. If I were a betting man - which I am - I would say that if you clean your throttle body and throttle plate and clear all your codes, your problem will be solved.

If I recall correctly from way back when I first experienced the same issues, the TPS is not a serviceable part, therefore you have to replace the throttle body assembly (at least in the '04 - I think that may have changed in newer models). I suggest cleaning the throttle body and plate first. see if that cures things before dropping the dough on the assembly.

 

You are truly wise. Thank you again. I am mechanically inclined so I hope your instructions can take me through this uncharted territory.

 

By the way. When you start the engine (after the cleaning process) it will run a little rough at first. This is normal and is the reason why you don't want to clear your DTC's before restarting, they would probably just reset.

Happy Hunting.

 

Is there a reason why some F150 owners remove the TB to clean? Doesn't seem as efficient as your way. Is there an advantage?
What cleaner do I use for the MAF? I'm guessing that should be cleaned while I have the unit open.

 

Hi Sako, I did not know that the TB plate would open without the engine running, do you know if the charge motion motor opens the runners when the TB is wide open and not running?

 

I am sure they have their reasons - pretty good ones at that - for the removal of the TB. I prefer to keep as many loose objects (bolts) away from the throat of the TB as possible. Also, it is recommended that you replace the TB O-ring anytime you remove the TB. My logic is - fewer steps - fewer things can go wrong or get broken. I have been doing this without removing the TB and have never suffered any adverse effects. Plus, not replacing the O-ring means fewer trips to the Ford House.


I use MAF sensor specific cleaner. Don't know if it really matters (vs. carb and choke), but I figure someone has invested in determining a solution that doesn't damage vital components.

 

Good question, Never really thought about that until now. As best as I can discern, The CMCV motor is controlled by the PCM and opens at a predetermined engine speed (RPM's). My Guess is - 0 RPM = no engine speed. Based on that logic - I would assume the answer is no.

The CMCV flaps are housed in the intake module and controlled by an electric motor. The CMCVs are controlled by an electronic motor, and open at a predetermined point as engine speed increases. At higher RPM, they do not affect the intake charge at all. This allows undisturbed maximum flow into the combustion chambers at wide-open throttle.

I love it when an old thread comes back to life.

 

I agree with your assessment completely. Once again you are very wise Jedi master. Thanks again for the great advice!!

 

Well, Spent the morning on the throttle body cleaning. I didn't have any MAF cleaner so I just went after the TB this morning. There was a ton of black stuff in the body and on the bottom of the plate. Cleaned it the best I could and re-assembled the duct work and electrical.

I ran the truck for about 10 mins and then shut off. Restarted and still got the engine light. I then took it for a 10 minute trip and ran her good.

Once I was back home I shut her off and to hopefully clear the remaining DTC's and then re-started. I still get the engine light and I don't have the computer to check to see what codes still remain and if any have dropped off.
I will most likely check on tuesday to see what codes still remain. I'm just unsure at this point if I did something wrong with the cleaning, should I have cleaned the MAF too or do I just have to reside myself to the fact that the TB may need to be replaced???

I've been looking at scary numbers for new ones with the TPS sensor on from Ford. Ebay seems to be anywhere from $230-345 on the OEM. There is also aftermarket....

If it is the TB is there any advice or suggestions on what I should do with replacement? I'm sure I will open a new thread if it comes to that as this one has been stretch beyond belief. Thank you moderators for not closing it yet!

 

For what it's worth, my '04 5.4L wouldn't start for me Saturday night (first time in 8 years that this has happened to me).

I had the wrench light and SES, no accel response, engine idled and that was it.

Turns out it was the TPS after reading some here and on other sites. I had my wife pick up a TPS on the way home; that was the wrong part because the connector didn't match. I also broke off the two screws because the part I got didn't include any instructions about the threads having locking compound and to use a heat gun to head the TB up. So I drilled them out the best I could after removing the whole throttle body.

Sunday after church I went by and got the *correct* part (for $40 more) and went home to put it on. I tapped the holes I drilled and found screws to match. I put blue loctite on them and reassembled it, hoping for the best. That did the trick, no more wrench and no more SES and it ran just fine.

I did take the time to thoroughly clean the TB when I had it apart. I was able to clean a bunch of leaves and junk out of the area in the fender where the intake pulls from. No telling how that affected performance, but I can say that it's all clean now.

Because there was a TSB for this, do you guys think I should go ahead and take it to the dealer to have the computer updated? What would they usually charge for this?

 

Chaos, Based on your post, I am lead to question your method of clearing codes. If you are just shutting her off, all that would clear would be soft codes. The hard codes are still there. Get an OBD II scan tool and clear all codes - be sure to document them before you clear.

Question. Is the truck running better, or is it still doing the same thing? Or am I to surmise that now it is just a matter of engine light?

Oh, BTW. Did not mean to drop out of the discussion. I changed my email address with FTE and could not reactive my account until this morning.

 

Thanks Sako!
I had that feeling about the codes so Sunday afternoon I saw another friend and we only had 2 codes out of the 4 in the computer this time. I believe they were P0121 and P2104. The other two cleared out after I cleaned it I guess.
We reset the codes and I've driven it about 50 miles and no light and no engine fail safe mode so far....
I'm still not sure if my cleaning was good enough so if it codes again I'm thinking of redoing the process u outlined.

Thanks again!!

 

I read all of the threads that I could find that are related to a problem I have been having with my 2006 Navigator with 97,000 miles.
Engine turns off when traveling, usually 35 to 45 MPH, city driving. Failsafe light comes on. After turning key off, the engine restarts immediately and runs fine, until the next time. Seems to be related to cold weather.
So, I cleaned the throttle body with specific cleaner and a microfiber towel while wife held throttle wide open with accelerator (key on, but engine not running). Also removed and cleaned the MAF sensor with specific cleaner.
Reinstalled everything, let stand about 20 minutes and started the engine and drove it.
So, now the engine will not immediately return to idle (750rpm). It seems to "hang" momentarily at about 1000 rpm and then abruptly, with a jerk, drops the idle to 750. I disconnected the battery hoping to '"reset" the computer or some other wish for mercy, but to no avail.
The Navigator is driveable but it is not running the way it should because of the high, momentary idle.
Did I hurt the throttle motor or the TPS with my cleaning? Has anyone else had this experience? (no check engine light is on).

Thank you for any help! Andy