Intermittent crank no start

[Doug Kuhlman]

My 2004 Expy 5.4 has been having an intermittent no start condition. It doesn't happen very often, but sometimes when you have gone for a drive and come back to restart it (still warm). Cranks, but will not start.
Go back later, and it fires right up like nothing was wrong.

The check engine light isn't on.

Any ideas?

Thanks,
Doug

 

[Hamfisted]

You might try swapping the PCM relay ( top right relay in fusebox...) with one of the other two lesser used in that top row and see if that changes things. On the '03 and '04 Expy's the PCM relay tends to get worn out, and swapping it for one of the others gives you a fresher relay. Or you can just order a new relay on Amazon or pick one up at the local auto parts store too.


https://www.amazon.com/Ford-F5TZ-14...keywords=Ford+PCM+relay&qid=1618428731&sr=8-4

 

[Doug Kuhlman]

Just following up.... It will not start at all now and the fuel pump is dead. With sadness, I am going to donate the truck to charity. The engine is still strong, 249k on the clock, but the rust is winning.

I found another '04 to replace it with only 102K miles and I still have my '08 too.

 

[Hamfisted]

Just following up.... It will not start at all now and the fuel pump is dead. With sadness, I am going to donate the truck to charity. The engine is still strong, 249k on the clock, but the rust is winning.

I found another '04 to replace it with only 102K miles and I still have my '08 too.

The PCM relay swap is a temporary fix to get truck running. The '03-'04 years had a huge problem with the fuel pump relay that's built into the center of the fuse box circuit board. If you're good at soldering you can fix it yourself for about $10 (for the new relay...). Or you can buy a new replacement fuse box that's been updated with the Panasonic relays. If the '04 you're looking at still has it's original fuse box you're going to have the same problems with that down the road. If you're '03 is in good shape otherwise, it's probably worth it to do the permanent fix on it. But if it's a rust bucket anyway, invest the money in the '04.






https://www.amazon.com/F8VF-BA-Rela...t=&hvlocphy=9011893&hvtargid=pla-884915441901

 

[Autumn Red]

Doug,
I just signed up right now to suggest the SJB fix or replacement, but I see that Mr. Hamfisted beat me to it!

I went through EVERYTHING for three years (two or three page list on notebook paper) before I found the problem with my 2006 Limited.

I am good with electronics but was unaware that there are relays inside the SJB which do not appear on any schematic I could find online. I was pretty mad about that. (Anything they call "smart", watch out.)

Also, after I finally got it fixed, within 6 months a truck hit it while I was waiting for a red light in Islamorada, FL Keys. @170,000 miles

I then purchased my 2012 XLT Premium with RWD, 55,000 miles, nice and clean.

Good luck to you, have a nice day!

Autumn Red

 

[Doug Kuhlman]

Autumn Red, Wow, that was some hit!
So, since I already have a replacement and am donating the car, I have lost interest in fixing it. But, you guys had me curious so I hard wired the fuel pump by unplugged the connector from the fuse box and running a wire from the battery to the green/yellow wire. The pump doesn't run and no start. So, I believe the pump is bad in my case.