2003 5.4 cranks but won't start

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fixitmyself

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I love my 2003 Expedition. Bought it used with 30K miles 5 years ago. Its an Eddie Bauer, now has 137,000 miles, 5.4 l, 4x4. ALL the bells and whistles including navigation, rear entertainment, cooled/heated seats, etc. About a year ago, the car wouldn't start sometimes (no crank) and the fuel pump relay (PCM relay number R203 white) would make a buzzing noise. When replaced with after market relay (black), it would then start, but it continued to burn out the relay (buzz) about every 3 months. Sometimes if I just tapped the relay while turning the ignition, it would start. This went on until about a month ago when the car would start dying on the road. I would pull over and wait a few minutes, tap the relay again and the car would eventually start. Finally, about two weeks ago the car wouldn't start at all. Luckily it was in my garage when this happened. I replaced the relay, but this time the car refused to start. I figured the fuel pump had been gradually going out, so I replaced it (expensive part and a monumental task!) and replaced the fuel filter. The car still doesn't start. Now, some of you are probably gonna yell at me for doing this, but I just had to know if it was a timing chain or spark issue, so I sprayed starting fluid in the throttle body and attempted to start the car. It fired right up, until the fluid was burned out and then it died again. So, I don't think its the timing chain and I know there is a spark. I tried to be as thorough as possible, but I will happy to provide more info in case I left something out. Any suggestions? Lou.
 

SPLFTW

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Well after all that put a meatter on the fuel pump and get some 1 to turn the key and chech ther is power ther (just to confarm your wiring) or blow out your fuel line might have crud in it (ez things)


Can u test injeckters
 

Racenut

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I love my 2003 Expedition. Bought it used with 30K miles 5 years ago. Its an Eddie Bauer, now has 137,000 miles, 5.4 l, 4x4. ALL the bells and whistles including navigation, rear entertainment, cooled/heated seats, etc. About a year ago, the car wouldn't start sometimes (no crank) and the fuel pump relay (PCM relay number R203 white) would make a buzzing noise. When replaced with after market relay (black), it would then start, but it continued to burn out the relay (buzz) about every 3 months. Sometimes if I just tapped the relay while turning the ignition, it would start. This went on until about a month ago when the car would start dying on the road. I would pull over and wait a few minutes, tap the relay again and the car would eventually start. Finally, about two weeks ago the car wouldn't start at all. Luckily it was in my garage when this happened. I replaced the relay, but this time the car refused to start. I figured the fuel pump had been gradually going out, so I replaced it (expensive part and a monumental task!) and replaced the fuel filter. The car still doesn't start. Now, some of you are probably gonna yell at me for doing this, but I just had to know if it was a timing chain or spark issue, so I sprayed starting fluid in the throttle body and attempted to start the car. It fired right up, until the fluid was burned out and then it died again. So, I don't think its the timing chain and I know there is a spark. I tried to be as thorough as possible, but I will happy to provide more info in case I left something out. Any suggestions? Lou.

Check out this link :

2003 Expedition no fuel pressure

http://www.fordf150.net/forums/viewtopic.php?f=1&t=82501

By the looks of the above thread they had the same problem, and the R203 is only part of the problem. There is another relay R303 which is actually soldered on the back of the relay center circuit board which also controls the fuel pump ( listed in book as dealer serviceable only ). That relay going bad could have caused the R203 ( one you have been replacing ) to overheat and keep burning.

Again check it out it sounds exactly the same as your problem.

Hope this helps.
 
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fixitmyself

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FUSE BOX!!! RACENUT got it right! Thanks for the link!! Your link was a perfect starting point!! After much more research I found another forum where a person was having the exact same problem. There I found out that there are 5 relays that are listed in the owner's manual, but owners are instructed to take the car to the dealer to deal with those. They are the R301 thru R305 relays and are hidden and soldered to the circuit board inside the fuse panel. Removed fuse panel, took it apart. The R303 (fuel pump shut-off switch, PCM fuel pump monitor, Fuel Pump) relay was fried (and literally melted). It was causing the R203 relay to burn. Solution: Gotta buy a whole new FUSE/BREAKER panel. I was going to have to buy it anyway because, after taking that fuse box completely apart, I don't think I would have been able to put it back together correctly. Pins were falling out of it as I took it apart and it would have taken me hours to figure out where they came from, even though I took pictures of the thing before disassembling it. The part number is 3L1Z-14A068-AA or 3L1Z-14A068-AB depending on vehicle manufacture date. It costs $265.00, but I found it for $193.22 after shopping lots of dealers in my area. It comes with all new fuses and breakers and more than likely will have to be ordered as most dealers don't stock them. So, I ordered it and I am going to slap that bad boy on in a couple of days and we'll see where that leaves us. I also found out that I need to check a bunch of places on the car to see if there are schaffed wires that are making contact with metal etc. Two of those places are the C pillar toward the top and in the engine compartment around all moving parts whre there are wiring harnesses nearby. Its going to be a crappy job, but it has to be done so that hopefull the realy doesn't keep burning out. I will keep you all posted. THANK YOU SO MUCH for taking the time to post your replies. The information really helped..... so far!
 

Racenut

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Glad it helped, hope you can get that wiring harness traced out. One good thing about playing Mr. mom for a while, is I have all kinds of time to sit in front of the computer :D ( Had surgery on my wrist and still healing so I am out of work for the time being ) That and I get to spend a lot more time with my daughter :D
 
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fixitmyself

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Fixed!!!!!

Changed the fuse box, checked ALL wiring (everywhere) and she's running like new! So, just to recap: I thought it was the fuel pump and replaced it and replaced the fuel filter to no avail. The car still didn't start. Removed the fuse box (located in the passenger side kick panel), took it apart and located the R303 relay, which is soldered to the circuit board inside the fuse box. It was fried. Replaced the entire fuse box, which comes complete with fuses, cover and cable that goes from box through the firewall and connects to battery positive terminal. After verifying all connections and looking for frayed wires (inside engine compartment, behind all pillars, under dash, all over the chassis, and under seats) and verifying that all fuel lines were secure, I turned the key and SHE FIRED RIGHT UP! A bit hesitant for about 3 seconds, but purring like a kitten afterward. RACENUT, I couldn't have done it so quickly without your help. THANK YOU! I probably would have gone in another direction first. I truly appreciate your response and everyone else's response to my original post. It's so good to have my Road Warrior back. Especially after driving an '08 Toyota Corolla for two weeks! LOL!
 

missy65202

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relay problem

We are having the same exact problems with our 2003 4X4 Expedition. Where did you purchase your fuse box from? The cheapest I have found so far is 290.00 from the dealership and thats before taxes.
 

ron1233

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relay problems too

Can someone explain to me where this fuse box (The R303 fuel pump shut-off switch, PCM fuel pump monitor, Fuel Pump) relay is located ?
 

elijahandshana

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I did all of the above including a new fuse box. It worked for a month. Last night, the truck wouldn't start. Everything came on but it wouldn't crank
 

Bedrck47

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check fuse 101 and 102 also make sure the starter relay is fully plugged in since you replaced the fuse block it could be possible that you didn't completely plug fuses and relays in

use a meter to check fuses
 

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