2008 explorer xlt sputtered / died unexpectedly- no start

[resq302]

Ok guys before you get out the flame throwers....... I'm trying to help out a co-worker with a problem with his wifes car.  Yes, I know.... its a Ford but its not my car.  lol. 

So, I've been working on my co-workers wife's 2008 explorer with the V-6 and I got it to fire up and run for a few seconds today before it died and won't start again.  I replaced the Fuel pressure sensor in the fuel rail (had received code P0191 before I started the repair) after I had to pull the intake manifold off.  That is when it fired up and then died and no start again.  When I turn the key to the on position, I'm not certain if I hear the fuel pump whirring for a few seconds or not but other cars I've heard them louder so it might or might not be working.  Aside from dropping the tank, and checking the wiring at the pump, is there any place to test and see if I am getting power to energize the fuel pump?  If I am getting power to the pump, what else should I check?  Is there any kind of fuel pump control module like there are on the F150s and the Expeditions?

Thanks in advance,

Brian

[Charger RT]

I drive mopars but fix fords and chevys to pay the bills. I am pretty sure that year explorer used a fuel pump driver. most explorers I've worked on had it under the rear of the vehicle bolted to the frame above and off to the side of the rear.

If you don't have the owners manual to map out the fuse box you can download a copy here. https://www.fleet.ford.com/partsandservice/owner-manuals/
are there any new codes? from the location of the sensor you replaced it has I'm guessing a 4.0?
Tim

[72Charger72]

I was going to say fuel rail pressure sensor also but you have changed that.
Most likely it is the Fuel pump driver bolted on the frame like Charger RT said. My buddy had one go bad on his 04 Explorer. There kind of a bitch to get off but better than dropping the tank.
Looks like this
https://www.autozone.com/engine-management/fuel-pump-driver-module/duralast-fuel-pump-driver-module/934958_0_0

[Charger_Fan]

Interesting, what does the fuel pump driver do?

[72Charger72]

Interesting, what does the fuel pump driver do?

The fuel pump relay is an electronic component that is found on virtually all vehicles equipped with an internal combustion engine. ... The fuel pump relay is usually controlled by the ignition or Powertrain Control Module, and when switched on, will provide current to the fuel pump so that it may function.
So basically an electrical relay for the fuel pump.

[Charger_Fan]

Interesting, what does the fuel pump driver do?

The fuel pump relay is an electronic component that is found on virtually all vehicles equipped with an internal combustion engine. ... The fuel pump relay is usually controlled by the ignition or Powertrain Control Module, and when switched on, will provide current to the fuel pump so that it may function.
So basically an electrical relay for the fuel pump.

I know about fuel pump relays, you guys were calling it a "driver", so I assumed it did something other than the usual relay function.

Sooo...it's just a relay, got it.

[72Charger72]

Interesting, what does the fuel pump driver do?

The fuel pump relay is an electronic component that is found on virtually all vehicles equipped with an internal combustion engine. ... The fuel pump relay is usually controlled by the ignition or Powertrain Control Module, and when switched on, will provide current to the fuel pump so that it may function.
So basically an electrical relay for the fuel pump.

I know about fuel pump relays, you guys were calling it a "driver", so I assumed it did something other than the usual relay function.

Sooo...it's just a relay, got it.

Well its a Ford !!!! So its a Fuel Pump Driver Module  

[gtx6970]

Ck'd fuel pressure with a gauge yet ?

get under it and place your ear to the tank and have someone cycle the key if needed.
A trick is take a screwdriver placed against your ear on one end and to the tank on the other works as well

[Charger RT]

Interesting, what does the fuel pump driver do?

instead of controlling fuel pressure with a regulator the driver controls the voltage going to the fuel pump. the computer moniters pressure and either raises voltage to the pump to increase pressure or lower voltage to lower pressure. Since the pump is now not running at full voltage all the time the pumps do seem to last longer.
this looks like a good video explaining operation.
https://www.youtube.com/watch?v=GqZTkso6kSg
Tim

[A383Wing]

did anyone check to see if the fuel pump inertia switch has been tripped to the off position?

Usually located in the passenger kick panel, can be reset by pushing the top button back down, it's like a circuit breaker

[JB400]

I agree that you should check fuel pressure at the rails first.  If there's no pressure, than the pump or something controlling the pump is kaput, or needs reset.

[A383Wing]

Another possibility is a bad MAP sensor. Try unplugging it to see if it starts. Unplug the electrical connection, not the vacuum hose

[Charger_Fan]

Interesting, what does the fuel pump driver do?

instead of controlling fuel pressure with a regulator the driver controls the voltage going to the fuel pump. the computer moniters pressure and either raises voltage to the pump to increase pressure or lower voltage to lower pressure. Since the pump is now not running at full voltage all the time the pumps do seem to last longer.
this looks like a good video explaining operation.
https://www.youtube.com/watch?v=GqZTkso6kSg
Tim

Tim, thanks for your informative post & link, that helps explain it a lot. 

[resq302]

Sorry guys, I have not had a chance to get back to working on the car due to trying to finish up my master bathroom renovation.  I'll probably get back to work on the car sometime this coming week.

The inertia switch has been checked and even reset but to no avail.  I have since printed out a bunch of schematics and testing procedures to try and aid in the repair for this.  One thing I did notice when I was working on it last was that there was mouse crap and acorns all under the intake manifold which kind of has me worried that the little vermon might have chewed up some wiring which is causing the problem too.   

[Charger RT]

One thing I did notice when I was working on it last was that there was mouse crap and acorns all under the intake manifold which kind of has me worried that the little vermon might have chewed up some wiring which is causing the problem too.   

it is quite possible there are a few lawsuits because of the soy based insulation the manufactures are using on their insulation while trying to be eco-friendly. It appears to be very attractive to mice as food. I have either fixed or replaced harnesses in three chevy police cars over the last few years one car twice. The main shop have been pulling intakes off new ford trucks lately because mice have been chewing wires on the 3.5 v6.
Tim

[lloyd3]

Fords equipped with the Triton engines from 2003 (and newer) seem to have a problem with cam phasers failing. It costs several hundred $$ to fix the problem.

[72Charger72]

I live in the country and it seems every winter the mice want to build under my 04 V6 intake. Recently I had to remove it to replace the fuel pressure sensor and I did not notice any chewing on wires. But the reason I had to change it is because it was dying randomly and then would not start. Let it sit a while and it starts again until it finally failed completely. They are a problem with ALL Fords 04-10. Just replaced another one on a 2010 Explorer. Rock Auto 38.00 for OEM local parts store 164.00

[lloyd3]

Dang it!

My next truck was going to be a Ford. Now I'm thinking it will be Japanese.

[resq302]

Well, after working on his car for two more days, I came to the conclusion that the PCM (power control module) otherwise known as the computer, seems to have taken a crap.  Starting back at scratch, I checked everything for power as the fuel pump did not seem to be kicking on.  Everything seemed to have power and when I put the key into the ignition and turned it to the on position, the PATS (passive anti-theft system) would blink rapidly.  Ok, this would explain why the fuel pump would not kick on.  I hooked my scan tool back up to the OBD port and now my scan tool was not connecting to the computer and said that there was an error in connecting to the PCM.  Funny, but it connected perfectly the previous day.  The only thing I can think is that the computer was on its way out and was throwing the codes that it did and causing the car to run, sputter, backfire, and then die.  I was able to get the car running for a very short time before it died and then would not run again.  This was just after I replaced the fuel pressure switch and put the intake back on.  After that, it would crank.  The following time I was there, it wouldn't even crank.  Now, I know Ford has had a tremendous amount of problems with their wiring as I had all kinds of issues with my 07 F150 and my wifes 08 Explorer.  Heck, even my Dad in his 09 F150 was having all kinds of electrical gremlins start at 30,000 miles.