I posted late last year "Has anyone ever had this happen" about a crank-no start condition that occurred. Well, last week it happened again when I got out of work. Crank, no start, just like before. Well, had it towed to dealer, tow truck set my truck down, the service advisor and I walked out to the truck and he tried to start it. Same thing, crank, no start. He said leave it and we'll check it in the morning. Well, the next morning it fired right up and fired up all day. So I picked it up and took it home. It is still operating normally. Again. Just like last time. Now, I may not be an ASE certified mechanic, and I may not be the most intelligent individual around, but I am not stupid. The fuel pump runs when it is told that the engine is running or cranking. With the key in the on position with the engine not running, the pump is not running. with the engine on, the pump is running. So what tells the fuel pump that the crankshaft is spinning and to run and send fuel to the engine? The crank sensor? Some other sensor? The service advisor told me that the computer does not monitor the fuel system so no codes are thrown. One other service advisor said that banging on the bottom of the fuel tank with a rubber mallet usually will get the pump to start working enough to get ya home. True or not? Maybe it could be the fuel pump, but within 3 years and less than 20,000 miles? So I'm wondering, what tells the fuel pump to run and send fuel to the engine? Like I said, key on without starting the engine, the pump isn't running. So what possibly could it be? Service advisor said fuel pump replacement would be over $900.00. I believe I can have it done cheaper elsewhere. Does anyone have any advice to offer? It's a bi**h when you go to the store and hoping the truck starts when you have a load of groceries including frozen food that you need to get home and into the fridge and freezer. Any help would be greatly appreciated. I hope you all understand just what I am describing here. Thanks in advance.
Dave
BTW, it's a 2002 F-150 Screw, 5.4 engine.

 

I have posted this many times.
The pump does not run with the key in run position without the motor running.
Here is how the system is designed to work.
At key on, the PCM is powered up.
A timer in the PCM operates a circuit to ground the pump relay for about 1 second only, then it opens the ground and stops the pump.
<<<<< It is designed that way to keep the pump from feeding a fire in case of accident>>>>>>
When cranking begins, the crank sensor tells the PCM the crank is turning.
This starts the timer again and regrounds the pump relay full time to keep the pump running.
In the pump circuit, the pump is powered through a relay and crash sensor from a seperate fused 12 volt supply.
The PCM only provides a ground to operate the relay as a slave, to connect 12 volts to the pump.
Has the fuel pressure been checked during a failure to be sure this is the prime failure?
Has the relay been changed and seating been exersized?
To check fuel pressure without running the engine, install a gage on the rail port and cycle the key to run only several times and look at the pressure. Is it 35 to 40 psi. If yes, the pump is not the problem, the motor should start if there is no other fault. If no, you have more work to do.
Unless a check out of the slave circuit is done for reliability and checks for voltage at the pump connector "during a failure", for poor ground etc you can't tell where the fault lies and the hassle will continue until you have some luck along the way.
I just cannot understand the towing to a dealer and then it starts as if there is no problem when there clearly is or it would not be there.
No one wants to do anythng;;;;; then have a good time with it.
It's like pulling up a chair and watching the truck to see if it fixes it'self.
Good luck.

 

Thanks for your reply. Now I at least know how the fuel system operates. Both times it was at the dealer, a fuel pressure gauge was hooked up and I was told that the pump was putting out the required pressure every time on startup. It's amazing to me that a dealer service dept was unable to find a problem. One would think that if anyone, they could find it, but who knows. Do you know what relay I should check, or should I check my owners manual? I don't know, all I know is that I am getting real tired of this. I do not think the fuel pump is the problem. It has to be something else in the system. Do you have any ideas besides chasing something that I wouldn't know where to look for it or find it? No, the relay has not been touched, pulled out, or cleaned.
Thanks in advance,
Dave

 

Here ya go.
Under the hood at the distribution fuse box, the cover latch is on the right side corner away from you as you stand at the drive fender.
The cover has the fuse and relay IDs embossed into the cover on the under side.
Pull out and reseat one at a time fuse number 10, middle of the second row of small fuses.
Next, do fuse #18 the same. Last one on the left, same row.
Next do the relay #301 right by fuse 18. It's tee shaped and called a full relay as opposed to the others you see that are called half relays.
You can download a copy of the owner's manuel from the Motorcraft website.
The fuse locations are shown on pages 207-213 for both the engine bay and under the dash.
If this is no help and lets you down again, you have to go to the pump connector and check it's seating etc. and do a relay swap with another same type relay location.
Matter of fact push seat all the fuses and relays.
Good luck.

 

I am having the same issue with my 2002 5.4L. It has been intermittent and only acts up in the winter. No issues in the warm months. If you don't hear the fuel pump buzz when turning the key it will not start. I have to cycle the key several times and eventually the fuel pump will come on and prime. I have also checked and replaced the relays but still experience the same issue.

Have you figured out what the problem is yet?

 

No, I haven't figured out what the problem is yet, but it happened again this evening. I just got home, had my truck towed to my house and have it in the driveway now. I got off work, it started fine. drove to the gas station by my house and bought cigs. Got back in the truck and it started fine. drove to the liquor store which is about 300 feet away from the Mobil mart. Went in and bought some beer. Came out and crank, no start! Now, I will say that the other 2 times that I had a crank no start condition, it just cranked freely. But this time, it seemed like it would want to, but sputtered and chugged, but no start, just like it did when it actually was the fuel pump. While I was trying to start it, in between pulling and re-seating fuses and relays, my battery wore down. Crap! So I had AAA come and take me home which is just about a quarter mile away from where I was. I was not about to take it to the dealer again. I can't afford a $900 repair bill right now. So, in a nutshell, it was acting different, like it did 3 years ago when it really was the fuel pump. My neighbor's son is a tow truck driver and he walked over and told me that if I buy the fuel pump, to search Craigslist for mobile mechanic and he said it would probably cost me about $100-$150 bucks to have him come out and replace it in my driveway. So now, after all the colorful language that I was spewing I have my truck home, but I do not think it will start tomorrow. If it does, I will crap my pants. I sure would like to hear anything that any of you would like to say. But I'm just bummed out right now.
Dave

 

I've seen some issues like that where a corroded wire was to blame. I would check the wiring on top of the fuel pump and chase it back as far as you can. I don't suspect the fuel pump itself. I've also seen an intermittant no start on a Lincoln Town car, no ryme or reason to when it would start or not. It would never die, just a no start. Turned out to be a partially pulled out wire out of the crank sensor. I can't remember if the principal is the same but sometimes its a stupid little thing like that.

 

Dave

I was able to solve my problem with great relief.. maybe this will help. Your issue sounds exactly the same as mine. I was able to diagnose the fuel pump as being the problem. You basically want to check to make sure you have power going to the pump in order to eliminate variables along the way.

The is a connector just before the fuel pump that you will have to get access to and check if there is power there when starting the truck. During my test there was power being delivered to the fuel pump before every start. When turning the key there was power at the pump and the pump did not turn on. I was 99% sure it was the fuel pump from the beginning, but I just wanted to check and make sure before buying a new one.

Ford wanted around $700 for a new fuel pump installed. I was able to get my own fuel pump and will install it tomorrow. Tonight I removed the bed and the pump is perfectly accessible from the top of the tank. It looks like you have already identified your issue as being the fuel pump.

Here is a tip to save you from having to get your truck towed home if it doesn't start: When you turn the key to start the truck you will hear the fuel pump prime indicated by a buzz from the rear of the vehicle. If you don't hear that buzz, it won't start. Keep cycling the key in the ignition. Not all the way to start the truck, but to the final step just before starting which should activate the fuel pump. You made need to keep cycling it for anywhere from 1 to 10 minutes, but the pump WILL eventually come on and you can start it. It is a goofy solution, but it works to at least get the truck started. At least it did with mine. Sometimes my truck would start on the first try and other times it would take 10 minutes of cycling the key.

Hope this helps- it's a big relief to get this issue taken care of.

 

Correct. You want to make sure the wiring on top of the pump is not to blame before spending money on a new pump.

 

My truck did this also i put a new fuel pump, fuel filter, fuel pressure regulator and it never started i had spark because it would hit on ether but all it ended up being was a Crank Position sensor. i had close to the same problem i think. Does your truck do this often because one time mine did this and i couldnt start it up i pulled off(shut off while driving) let it sit for a half hour then started right back up. id look into the CPS its 25$ and takes 25 min to change vs all the bull of dropping the tank. all u have to do remove ac compressor then bam pull the sensor out put a new one in!