Campe542

I'm new here but have stalked the forums before for answers to my questions but am struggling with this one. I have a 2006 F150 with 5.4 triton. Recently going down the highway and it stalled out on me. Could not get it restarted so towed back home. Got it to start once the next day slow to respond to the gas being depressed but eventually reved up then died when I let go of gas. Would not restart after that. Put pocket code reader on and only showed a miss in 8. Did not quite make sense to me because I thought it would just run rough with a miss but replaced the spark plug anyways. I also swapped coil 4 and 8 in case the coil was bad as it would be easier to get to. Same issue got it to start once rev then die. Begin searching forums for other ideas and how to test fuel pressure since I could not find a valve on the fuel rail. There were several mentions of checking the fuel pump module above spare tire so I pulled that. There was a corroded hole in the back so I replaced it and while I was at it I replaced the fuel filter. I never did a fuel pressure test but can here the fuel pump when I have my ear back by the rear tire. After all this it starts more regularly but I have to depress the gas to get it to start. As long as I keep gas depressed it runs but still seems rough. When I let go of gas idle drops low struggles for about 10 seconds and dies. After it dies low oil pressure has started to show up on the display this was not happening before. Checked oil and added a quart to be safe still displays after it dies. Searching forums again someone mentioned cleaning changing IAC valve. After a little more research realized my truck does not have that and that it's part of the throttle body assembly. I have now pulled the throttle body and will clean it shortly just have to go get the correct cleaner but it does not look that dirty. Not sure if I should buy a new throttle body but hesitant because it's kind of expensive and not sure if that's even the problem or do I go back to the only code I ever got which was the miss in 8 and maybe replace all plugs and coils? Any help or ideas from someone more experienced than me would be greatly appreciated.

Recap
Code for miss in 8 replaced plug cleared code never had another code
Replaced fuel filter
Replace fuel pump control module
In process of cleaning throttle body

Starts when throttle is depressed still seems to run a little rough let go of throttle and struggles at idle for about 10 seconds and dies low oil pressure displays after it dies. Still no other codes ever.

Additional info
This truck has around 185,000 on it but I have only had it for about 4-5 months. Haven't had any problems with it before. Always started quickly and easily.

techrep

iTrader: (1)

I would replace all 8 plugs with motor craft SP 515.. replace all coil boots and springs .. clean COP contacts.. light coat of dielectric grease on both sides of the boot ends.. not the springs. Clean throttle body and MAF sensor with proper cleaners. Go from there.

Campe542

Thanks for the response. I just cleaned the throttle body before I saw I had a suggestion. Forgive my ignorance but what are the COP contacts? I that the coil where it plugs in to the electric connector? Heading back to store to get plugs, boots, springs, MAF cleaner, and dielectric grease. Just to confirm not replacing could just boots and springs correct?

After throttle body was cleaned it started without depressing accelerator and ran at about 1000-1100 rpm idle for about 20 seconds before slowly dropping over about 10 seconds and dying. At higher idle still seemed to run a little rough but much better than before.

techrep

iTrader: (1)

You did remove the throttle body prior to cleaning it ?

Campe542

Yes I completely removed throttle body and cleaned while on work bench then reinstalled. I also have since cleaned MAF sensor. No change from throttle body cleaning. Starts with out pressing gas runs at 1000-1100 rpm for about 20 seconds then over 10 seconds rpms drop then it dies.
Purchased boots and springs but they did not have plugs so I have to go to another store across town. Being Mother's Day I have to go out of town to see my mom so I'm going to pick the plugs up on my way out so I won't replace boots and plugs until tomorrow after work.

Little confused by the how to check transmission fluid video you linked. Is that a possible issue with the engine?

techrep

iTrader: (1)

I'm confused.. I did not link anything to you..

Campe542

Maybe it's one of the advertisements they squeeze in. It's no longer there. It was a YouTube video from jiffy lube on how to check transmission fluid and top it off

Campe542

All plugs, boots, and springs changed. While it probably most definitely needed that, one of the spark plug tops was actually bent, it is still doing the same thing. My stepdad suggested I do a full fuel pressure check even though I'm hearing that pump run. Said he had one before that would run but was on it's last leg so It was putting out no pressure. So that's on my list of things to get tomorrow a pressure checker and figure out how to test since I don't have a valve on the fuel rail. Any other suggestions?

toostroked

Sounds like the fuel pump control module. That isn't the correct name, but it is located above the spare.

Campe542

I replaced that already.