Dealer, locksmith or do it yourself. You can wipe a program keys with forscan.

 

 

It started up just fine this morning...I'll keep trying. The theft light went out.

 

 

 

I just solved an intermittent crank/no start on my 03 F150 supercrew 5.4L. The intermittent part drives you crazy. Mine ended up being an intermittent fuel pump and a faulty PCM. You need to verify if the PATS is working correctly....make sure it is not flashing during cranking.....sounds like yours is ok as it starts and runs fine (now and then) as mine did. Does your fuel pump run (prime) for the 2-3 secs every time the key is switched on? Mine was intermittent and I traced the problem to the fuel pump by checking voltage at the inertia switch. It was getting the 2-3 sec power from the PCM every time, yet the fuel pump only ran every 5th cycle or so. New fuel pump cured that. But I still had intermittent starts. I also verified I had no spark and no fuel injector firing. Really looked like a bad crank sensor or crank sensor connection, so I verified that signal was getting from crank sensor to the PCM connector. At that point, I had the truck towed to the shop along with the ebay PCM I had purchased a couple yrs earlier (that's another story....) He, too, suspected the Napa crank sensor I had replaced so he ordered a Motorcraft. Still wouldn't start. Replaced the PCM, flashed it and bingo.

I gather that PCMs rarely fail as mine did, so suggest you test the basics first to rule things out. Autozone will lend (no charge) fuel pressure test kit, noid lights to check fuel inj pulses, spark tester, etc. Also check your fuel pump relay and PCM relay. My power window relay was identical to the fuel pump and PCM relays, so swapped those out to verify it wasn't a bad relay (I knew the power window relay was good). Will be interested to hear how your problem gets resolved.

 

Just a comment so please don't get excited.
You say you had PCM powering the relay everytime but the pump would not run every 5th time.
So a replacement PCM was the answer.
Under that scenario, can't be!
The PCM operates the pump relay that closes contacts to cut though power from a separate fused supply.
Since the pump relay operated everytime but the pump did not receive power or run, how do you square with that by replacing the PCM as the problem?
Or did I misunderstand?
Just wondering If my comprehension is going bad.
Good it's solved though.

 

Bluegrass: I had 2 problems, a bad fuel pump AND a bad PCM. Both were intermittent. The way I diagnosed the bad fuel pump was to check voltage at the inertia switch....every key-on cycle, I had power at the inertia switch for the 2-3 sec prime cycle. The pump, however, would only run (prime) every fifth cycle or so. Changed the fuel pump and it primed every key-on cycle. So the fuel pump logic in the PCM was working as designed. I was still getting intermittent starts though.

Once when it started, I got code P0320 which generally points to the CKP. That's when I checked for signal from the CKP at the PCM connector.....it was good. So I assumed fault was in the PCM reading the signal from the CKP. The shop also saw the P0320 code and that's why he changed to a Motorcraft sensor. It did not fix the problem. So he flashed and changed my replacement PCM and success! (I was careful to ensure that the PCM I bought was a perfect match for part no., catch code, and hardware code.)

Note: I decided the forescan process was over my head, so that's why I took the truck to a shop. He charged me 1 hr labor to diagnose and $70 to flash and replace the PCM I gave him. Got out of there for $180, which I thought was very fair. He's a good guy....most shops won't touch a junkyard part you bring in.

 

 

When you get it back, we'd love to know what fixed it.

 

So I haven't taken it to the shop yet because if I turn the key to the on position W/O starting and letting it sit for ten or more seconds, it starts every time. So now I have no idea what's up with it. With that in mind, I wonder if it's taking a little time for the fuel pressure to build up... maybe the fuel pressure module? Again, this is way over my head since my mechanical prowess is with classic VW's. Never worked on a vehicle with all that computer stuff.

 

sThere is no fuel pump module.
It is a two pipe system with a feed and return back to the tank..
The regulator take fuel pressure from the main rail and drops it to about 35 psi.to feed the fuel injectors.
The pump does not run much beyond about 3 seconds. This timing is controlled by a timer in the PCM.
The only way for the pump to run beyond the timer limit is burnt closed relay contacts.
Put a pressure gage on the test port and see what's gong on.

 

Murf - you can borrow a fuel pressure test kit at Autozone for no charge (you leave a deposit and get your $ back when you return). As Bluegrass said, the PCM runs the fuel pump for a 3 second "prime" cycle each time you turn the key on to pressurize the fuel rail. Do you hear the pump prime each time you turn key on? Mine did not run every time and sometimes when it did run, my fuel rail would only pressurize to about 10 psi. You need to see about 35 psi with one prime cycle at the test port....otherwise the fuel pump is suspect.

BTW, you can buy a fuel pressure test kit at harbor freight for like $16. I did this because the Ford adapter in my Autozone kit had a bad seal and would leak. The harbor freight kit has an excellent adapter hose for the Ford connector. (The Ford connector/schrader valve is the same thread as a tire valve stem)

BTW #2: The worst part of a fuel pump changeout is getting to all the disconnects (hoses and connectors). Some of the hoses are stubborn. After that, it was easy. I ended up taking the entire filler neck assy out to get it out of the way. And much easier if your tank is near empty....tank is surprisingly light and easy to maneuver when empty. (Mine was almost full...had to siphon out 22 gal.) Most common suggestion I rec'd was "take the bed off, much easier". Not an option for me because removing the bed does not get you access to the fuel pump on a supercrew.