fuel pump trouble

[sfoster]

My daughter's 99 Contour (built March 99) has an intermitant no fuel pump operation problem. I replaced the fuel pump about a year ago. It has the return type fuel system. About 4-6 weeks ago it started having trouble. The fuel pump would not be operating when first turning ignition on. She would look at the pump wiring and wiggle it. Then it would start. Yesterday when I finally was able to catch it acting up. The pump was only getting 7 volts as measured at the pump plug. I first tried moving one wire at a time. No amount of wiggling changed anything. When I powered the pump with my 12V battery pack it worked. Then I pulled and reseated the fuse and relay just to ensuure that they were fully seated. Then I reset the ECU by disconnecting the battery. I forgot to check the fuel pump operation after reseating the fuel and relay. By at any rate then I reconnected the battery it works. Finally my questions, What is the fuel system operation? Does the ECU directly drive the fuel pump or is there a fuel pump driver module like my 2K focus? What would cause the voltage to drop to 7 V? The obvious thoughts are a wire broke and not making complete comtact. What else should I check? Could it be the ECU? If I replace the ECU with one from a Junk, Opps Auto recycler, does that need to be reprogrammed by Ford or is it plug and play? Thanks in advance.

 

[gorman]

Hey sfoster;

A poor connection on either the live feed or the ground could give reduced voltage reading.

As far as i know only the non return fuel systems are driven/controlled by the PCM.

Don't buy another PCM. it is not the problem.... more likely a loose connection or loss of wiring insulation.

Just so you know, the plug and play PCMs are the ones with external PATS. If your PATS system is internal, you will need to get your keys programmed to the new PCM..

mucho costo

The info on PATS is stickied .. not sure where .. search if you really need it..G.

 

[sfoster]

Thanks, for the quick reply. Her Contour is the non-pats type 2L. I should have put that in the post.

 

[gorman]

Well that's good, one less thing to worry about. Still think you are looking in the right places with wiring and fuse/relays.

let us know how you get on ....G.

 

[terryford8]

Hope you don't mind if I add that my car wasn't starting..i bought a new fuel pump
Turned out the very thin fuel line that enter the (Under Car) Fuel filter had a kink in it
I replaced all the lines leading into the filter...no problems since
Understand this is an electrical issue but figured it might help others reading the post
my car 1999 merc mystique v6 with two line fuel pump

 

[CSVT#49]

G hit the nail on the head IMO. I'd start poking around looking for corrosion on the connections. I'd dab in a little dieletric grease in the connections to assist with fighting corrosion. Might want to double check the connections on the pump assembly in the tank as well. I'm most familiar with the return style systems so not quite sure what the returnless style pump assemble connections look like.

Also if you went through changing out the fuel pump I'd look at replacing the fuel filter also if you haven't done so already. If that is clogged a bit your making that pump work a lot harder, which will put a larger current draw on the electrical system.