I am pretty sure this is the problem with my F150. But I have called every part store asking about this part & no one has a clue. If I go into Advanced auto or any part store what do I ask for?
I own a 03 F-150 Supercrew. 4.6l - 2 wheel drive.

Thanks so much.

 

I understand why they have no clue. Who told you your problem was the PCM Power Relay? And what exactly is a PCM power relay? Been a while since April 1, I hope you haven't been looking since then.

 

So what controls the power relay?????

 

If you don't know what a PCM Power Relay is, you should follow Mark Twain's advice.

Depending on the parts store's computer, they may call it the EEC or the ECM (both acronyms are synonymous with the PCM) relay. In any event, it is the master relay that controls operating power to the vehicle computer and if must be good for the truck to run. When they start to go bad, all kinds of weird things happen (intermittent stalling, no starts, etc).

Go to Advance Auto and ask them for a Borg Warner (BWD) # R3177 relay. It's around 12.50 retail and is a generic relay 30A relay. The same relay is used in several other functions in your truck including the fuel pump relay.


The ignition key switch.

 

Oh, THAT relay. What was Mark Twains advice? Ask for an EEC or ECM? That guy was really ahead of his time wasn't he? How did he know about the EEC and ECM? Must have been smarter than the average parts guy.

 

I dunno, but I suspect it *may* be the tenth on one in this list:

http://www.quotationspage.com/quotes/Mark_Twain/31

 

new to forum and I know thread is a little old but for anyone struggling with pats crank but no start issues here's my experience it may help some. My truck would start when not used for awhile after shutting off it would crank but not restart. Theft light blinking. I replaced fuel pump no change. Before u waste time and money like me check all fuses relays and diodes having to do with pcm. I highlighted in manual all fuses relays and diodes in my manual then started checking. Pcm diode turned out to be rusted switched with ac diode and viola fixed. I spent hours replacing fuel pump and searching for bad grounds but please check both ur fuse panels first Hope this helps someone