I have a 2005 F150 XLT 5.4 that doesn't always start.
I've been having this problem for over a year now.

Sometimes it will start, but sometimes it won't. Seems about every other, or perhaps every 3 days it just will not start. Then, if I wait a few hours, it'll start.

I've replaced the fuel pump, fuel filter, mass air flow sensor, fuel pump driver module, starter and the battery.

None of this has seemed to effect it.

Lately I've found out that if I put the truck in neutral, then while cranking I go to park (going through reverse) it will start. Sometimes not on the first try, but after a few attempts it will start.

It should also be noted that when it does start, often it'll make some loud noise RIGHT before it starts up. Sounds kind of like the starter grinding. If it doesn't make the grind noise, the other thing it may do is all the lights and everything turn off for an instant (half a second) then come back on and start.

I'm really lost as to what to do. I've been thinking that it may be the transmission range sensor, but I really don't know. I don't want to keep spending money replacing random parts, in hopes of fixing it. I'm on the 3rd starter, because of all the cranking I have to do when it doesn't start.

Thanks

 

Hi,

Just guessing a little, but it sounds as if it could be
1. wiring -- bad ground or similar
2. misalignment of your starter -- that could cause it to draw more current.

It might be worth while to try and get the starter current measured -- see if it's runnning pretty high.

Otherwise you could look at your cables and grounds. Try to measure the voltage difference from the battery post to the framw while it's cranking.

Things like that.

Good Luck,

hj

 

So it cranks real strong, but won't start?

Mine had troubles starting a while ago. It would randomly sputter after cranking and then die. New spark plugs fixed it completely. When I looked at them, the plugs were visibly worn out though they only had 65K on them. No way they would have made it to the factory replacement interval of 100K

Noises don't sound too good. Is it possible the starter isn't retracting from the flywheel fast enough?

 

At near the 100k mark I had the plugs replaced by the dealership. One of them had welded itself into the block and broke off, so they had to pull the whole motor.
Do ya'll think it likely that perhaps a wire was poorly installed or something? I hate to sound ignorant, but I really don't know how I can check the grounds.

And yes it cranks real strong. I don't think it's the starter not retracting, because the noise happens before it starts, not after.

I don't understand how it could be a bad ground or something (though I'm more than willing to search for it) considering that I can get it to start by cranking and going from neutral to park. Not always on the first time, but within a couple it'll fire up.

 

Here's video of it.
Not sure if you can hear it or not, but at the end, it starts.

http://www.youtube.com/watch?v=STQ3A...ature=youtu.be

 

If you leave the truck in neutral, does it start without shifting through reverse?

Here's a wild azz guess--of course no guarantees, so don't jump at replacing parts!

I'm looking at my schematics and there's a thing called a Digital Transmission Range Sensor (DTR).It's wired to the PCM and starter circuit. If the selector/tranny are in Park or Neutral, it appears it allows a start.

So something to check would be the shift selector connection and this 12-pin connector 'C167' supposedly coming off the driver side of transmission just above the tranny pan. It has the shift selector setting and 4 other switched connections feeding the PCM and starter circuit but it's not clear what they all do. Maybe some kind of tranny feedback. Try reseating that connector and look for corrosion first.

 

That's the problem, I don't have the money to be replacing parts if they don't fix it.

No it does not start in neutral without shifting through them.

I've checked out the DTR, with it unplugged it will not crank at all. It's not stopping it from cranking, so I don't see how it could be inhibiting the starting. I cleaned it with electrical cleaner earlier, but later this afternoon the truck would not start (until i tried the shifting through P-R-N.)

 

Are you switching keys between starts? Are you using programed keys. The PATS module in the column may not be seeing this.

 

I have not been, though I have tried before to see if it was possibly a bad key.
I have two keys that came with the truck from the dealer when I bought it new. They are the only ones I've used.

 

Sounds like it's more than likely a crank position sensor.