will a new lock cylinder with new key need to be programmed with my pats?

[biggiesize]

So heres the issue.Im having a sporadic cranking issue.I have to turn the key anywhere from 8-10 times for the fuel pump to kick in.Its not the fuel pump or relay.I have narrowed it to something being wrong with the lock cylinder.If i purchase one from autozone that comes with new keys will it work with my pats system or will it the whols system have to be recoded?

 

[SoNic67]

The lock cylinder doesn't have electrical contacts except the sensor for the "key in lock". All the power contacts (including the one for the pump) are located at the base of steering column, actuated by a plastic push-rod.

However, the fuel pump process is like this: You turn the key to "on" (not "start"). PCM reads that and commands the fuel pump for a few seconds to prime the pressure, then, if the engine is not running, the PCM turns off the pump. The voltage for the pump goes trough the inertial switch (kicker panel passenger side) that can interrupt the pump circuit in case of an accident. There is nothing directly connected to the key.

If you need to prime the pump several times, the pump's check valve is bad. Check valve maintains the fuel line pressurized when the engine is shut-off, otherwise the rail pressure will "push" the gas back in the tank.

 

[koda2000]

So heres the issue.Im having a sporadic cranking issue.I have to turn the key anywhere from 8-10 times for the fuel pump to kick in.Its not the fuel pump or relay.I have narrowed it to something being wrong with the lock cylinder.If i purchase one from autozone that comes with new keys will it work with my pats system or will it the whols system have to be recoded?

Yes, the new keys will need to be programmed. If you have 2 working (non-cloned) keys you can program new keys yourself, otherwise you'll need a locksmith or Ford dealer to do it. There are options to doing this (like swapping the chips in the keys).

Question - What makes you think the key switch is the problem and not the ignition switch itself? These are 2 different parts. If you change the ignition switch it has nothing to do with the key switch, which is just mechanical. The ignition switch is the electrical component.

 

[biggiesize]

I found a diagram of the rod that runs down to activate the switch thats mounted halfway down the steering column.I didnt know that was the ignition switch.So does the ignition switch (not the key switch) activate the fuel pump?Sometimes I hear the fuel pump the first turn of the key.Other times it takes a combination of wiggling the key cylinder and turning the key 8-10 times before the fuel pump engages to let it crank.After the fuel pump finally engages,it runs fine.i could drive it for 3-4 hours nonstop.So im positive the fuel pump isnt the issue.

 

[koda2000]

I found a diagram of the rod that runs down to activate the switch thats mounted halfway down the steering column.I didnt know that was the ignition switch.So does the ignition switch (not the key switch) activate the fuel pump?Sometimes I hear the fuel pump the first turn of the key.Other times it takes a combination of wiggling the key cylinder and turning the key 8-10 times before the fuel pump engages to let it crank.After the fuel pump finally engages,it runs fine.i could drive it for 3-4 hours nonstop.So im positive the fuel pump isnt the issue.

Well, there's no fuel pump electronics related to where the key goes. Power is controlled by the ignition switch.

I wouldn't be so sure the problem isn't with your fuel pump. When they get old and the brushes are worn, they can work intermittently. I had this happen on one of my trucks a few years ago. As soon as the weather turned cold I had to turn the key multiple times before the pump would run. Once it was running it would work fine all day until the next morning. How many miles on your fuel pump?

Next time it wont run try thumping the bottom of the fuel pump with a rubber mallet, or 2x4, near the rear bottom of the tank. You'll see a small tear-dropped shape in the bottom of the tank. That's where the fuel pump is located.

 

[Runnin'OnEmpty]

I agree with Koda and Sonic in that it's probably worn brushes in the fuel pump causing the no-start. Same thing happened to me with a Ranger. It was hard to get the pump
to start but once running would run fine until shut off.

I cut into the old pump and found the brushes had worn
grooves into the commutator causing poor electrical
contact.

 

[biggiesize]

I went ahead and put in a new fuel pump today.So far it has fired up every time,so fingers crossed.Odd thing was tho,I bench tested the old fuel pump with a pos and neg and it kicked in every time for probably 30 times.So who knows if that was even the issue.It might show up again tomorrow.But with 233,000 miles on the old fuel pump it needed one as preventative maintenance anyway.

 

[koda2000]

I went ahead and put in a new fuel pump today.So far it has fired up every time,so fingers crossed.Odd thing was tho,I bench tested the old fuel pump with a pos and neg and it kicked in every time for probably 30 times.So who knows if that was even the issue.It might show up again tomorrow.But with 233,000 miles on the old fuel pump it needed one as preventative maintenance anyway.

Just for goofs, try putting the old pump in the freezer for a few hours and bench test it. I have experienced 3 fuel pumps working intermittently as soon as the weather gets cold. Currently my '00 5.0 XLT is doing this. It did it several times last winter, but has been fine all summer. Now that the overnight temps are getting into the low 40's it's acting up again (requiring several turns of the key before you hear the pump prime). I need to install a new pump, but it's not a priority right now, as this is the family's "spare vehicle". I've installed 3 fuel pumps in 3 different Explorers/Mountaineers in the past 9 months... I've gotten very good at this job. This will be my 5th Gen II fuel pump change. All my fuel pumps started acting up at about 200K +/-.

Please let us know if this solves your intermittent starting problem.

 

[biggiesize]

The freezer is a great idea!I did notice that it was worse on cold mornings and it just started acting up this month as it got colder.

 

[biggiesize]

Looks like it was def. The fuel pump.Thanks for all the input guys.

 

[koda2000]

Looks like it was def. The fuel pump.Thanks for all the input guys.

Cool! Congrats

 

[biggiesize]

I would have never guessed that fuel pump could work intermittently.I thought they were either good or bad.

 

[koda2000]

I would have never guessed that fuel pump could work intermittently.I thought they were either good or bad.

Yep, I've had 3 work intermittently and 2 just go dead all at once. It's pretty common for electric motors to work intermittently as they're wearing out.