Tim in Corpus

tell them to hook up a smoke machine to verify the intake manifold leak. i have one and find leaks that would not show up by just spraying carb cleaner and looking for rpm increase..fords also can misfire and not set the check engine light on they are bad about that. you could have a bad coil and it wont show up with a cheap scanner. they need to have one that shows individual misfires in what they call Mode 6 data non continuoes monitors . if they dont have a smoke machine and dont have a scanner that can do this just go somewhere else. seems like people at the dealership should be able to figure this out. also fords can have what they call torque shudder which is when the transmission bucks just a little bit when going inbetween drive and overdrive.

youngff

This sounds exactly like my wifes '07 Expedition. I also noticed it cruising right around 45mph going up a slight grade. Yesterday, however, I noticed it again but at 70 mph. It was so annoying, I would accelerate to 10mph above the speed limit and then let it coast down so I didn't have to feel the jerkiness. I was thinking at had something to do with the TPS or the fuel system but after reading this, I have no idea. Someone PLEASE post a solution!

coleslaw01

i have the same issue going on with my 05 fx4. I have asked a few tecs. and read a few post on here and the most common answer i got is the torque converter locking and unlocking in overdrive

mjlater

I have the same exact issue but I am getting a p0430 bank 2. What I have read so far is this is related to bad coil. The OP said he replaced all of his so that eliminates that. Please keep us updated on your posting!!!

sinclairgraphics1

Did anyone find a fix to this??? I have the same damn problem between 55-60mph with the motor bogging and moaning. Mine is a 2004 with a 5.4 146,000 miles. If I give it more gas I can get out of it. I have done every bit of maintenance and spent several thousand dollars taking this to numerous shops and dealers. No codes, no nothing. WTF!! Is this so impossible to fix or find the problem?

ushydrographics

I am having the same issue. Above is the screen shot of my sensors. Does anyone have the answer to this?? Please help. I am going crazy. I have done the foam gasket, changed plugs, changed air filter changed tps. Dont know what else to do.

Thanks in advanve!!

supramahn

After reading through the threads associated with this and trusting the calibrated butt cheeks of my local mechanic, I went with a torque converter. 16 hours later at the hobby shop on base it was changed but not fixed. It did sort out some other issues, but not the main one.

I started leaning towards a mild misfire after digging through some other forums and went ahead and ordered 8 coil packs from AutoZone. Changed them out as well as finding one of the connectors damaged (the lock was broken and the rubber seal split and somehow wedged in front of one of the pins. I removed the rubber and zip tied the connector in while I wait for the new one to reach me(overseas at the moment). and Voila! Problem solved!!!!

Hope I can save everyone some headache and trouble


05 5.4 XLT with 155K

Arvina

A friend of mine had this same problem on his wifes mustang. His mechanic told him it was the fuel pump of all things. He replaced it and it fixed his problem. I am now having this problem and and considering the fuel pump.

redfishtd

Mine was shutting down suddenly at different times usually when throttling up . . Codes pointed at TPS, changed it out but still acted up. Read about the new throttle body number 8L I believe , bought new one on ebay 200 bucks with new tps on it . Been 5k miles no more problems . If The motor circuit on the throttlle body disagrees with the TPS and the gas pedal sensor to the computer then the engine shutsdown or goes into failsafe . I imagine other symptoms can happen , there a whole circuit board on the throttle body drive motor to decode the throttle pulses from the ecm . Lots to fail there and I jumped on it when I heard about the bad 3L series throttle body .

Brian Sheen

2005 F150 5.4L. 106K miles. Same issue. What I can't believe is this seems to be a large scale issue that there is no answer for?! Frustrating!!!!

I took mine in because of this issue. Replaced plugs with no success. In fact after getting it back I now have an exhaust/fuel smell in the cab when not in motion. Still hesitating.

Put all new coils in...NOT fixed
Put all new injectors in...NOT fixed
Put new fuel filter in...NOT fixed

I reached out yesterday to another member of this forum that said he took his in and they found one of the Catalytic converters to be bad. That solved his issue apparently. He has not responded to my PM.

I am highly considering this option due to the odor of fuel/exhaust that has accompanied the spark plug change. Thinking maybe this is the source of both problems.