cb8892 Report post Posted March 11, 2014 Have a 2007 Edge fwd. Have had no problems until recently would not start shortly after being driven a few minutes earlier. Could not find similar thread. Turns over fine, not a battery issue. Fuel pump not making noise. Plenty of fuel in tank. Checked and switched around relays and fuses with no apparent fix. Jiggled wires above fuel tank/pump, with no apparent fix. Tapped (banged) on bottom of tank... seemed to work... turned key, fuel pump comes on, car cranks and runs fine for another week without even a sputter. Same thing again... no fuel pump noise, car not starting after being driven earlier that morning... did all of the above again... relays, fuses, tank wires, banging on tank... and this time reset the inertia switch in the back quarter panel. Nothing. Sits for 2 days, go to put in nuetral and roll back... put key in, turn key on, pump runs, car cranks and runs fine. Trying to avoid removing fuel pump from tank if there is any other possible solution. Any other thoughts or better ways to test relays for intermittent failure? Also, any idea what the fule pump diode is/does? Located with the relays and fuses, but just looks like a small black opaque fuse. I think it keeps power from traveling one way, but not sure if it can fail or how to check. Thanks, cb Share this post Link to post Share on other sites
akirby Report post Posted March 11, 2014 You can check the voltage on the fuel pump relay and the leads going to the pump. When it won't start if you're getting voltage to the fuel pump but you have no fuel pressure (verify at the fuel rail with a gauge) then it's the pump or the wiring at the pump. Could be a bad/loose connection to the pump or the pump itself is bad or clogged up. Does it tend to do it when the tank is close to empty? Share this post Link to post Share on other sites
cb8892 Report post Posted March 11, 2014 akirby, thanks. no it has had over a qtr tank both times. i tend to lean towards a electrical vs the pump being clogged because it cranks each time i hear the pump spin, but not at all when no pump noise, but not sure. Anyone familiar with hardwired connections inside the tank at the pump going bad? How likely a pump going bad would sometimes come on and sometimes not vs. just failing? Share this post Link to post Share on other sites
cb8892 Report post Posted March 14, 2014 So I found the problem. All relays, fuses, etc, checked out fine. Removed the tank to check the pump and found faulty/bad/melted wiring harness... inside the tank on the existing fuel pump. Not exactly what I would like to see inside a gas tank!! See pics. Replaced pump. Works fine. Btw, I did also find access panel (see pics) where it looks like the pump could have been removed from inside the car... but not sure that would have been any easier by the time you removed the seats, carpet, etc and had tiny opening to break pump lock ring loose. The tank dropped fairly easily... put the back of the car on ramps, removed rear half of exhaust (1 clamp and 4 rubber hangers), 6 tank mount bolts, moved a couple brake cables out of the way, disconnected fuel line, evap hose, tank fill hose, let it down easy with floor jack and rolled/slid out the back. Hope this helps someone else. 1 Share this post Link to post Share on other sites
akirby Report post Posted March 14, 2014 Could be a bad/loose connection to the pump Share this post Link to post Share on other sites
akirby Report post Posted March 14, 2014 BTW - this was most likely caused by running the pump low on fuel (the fuel actually cools it) or debris that clogged up the pump causing it to overheat. It could have just been a defective pump too. Share this post Link to post Share on other sites
WWWPerfA_ZN0W Report post Posted March 14, 2014 Add this to the list of various electrical connector issues, not a good place to have it, agreed. Share this post Link to post Share on other sites
ls973800 Report post Posted March 14, 2014 Any rust on top of the tank like other owners of earlier Edges and MKX's have reported? They were saying something over $1000.00 to replace the tank. Share this post Link to post Share on other sites
Ravenrick96 Report post Posted June 4, 2015 I know this post has been here for a while, I just wanted to let any future readers know that there is an access plate under the left rear seat. The seats are very easy remove, definitely easier than dropping tank assembly. I found the same issue of a burnt pin in the electrical connector on top of Fuel Pump. Hope this helps someone as this post helped me. I have a 2008 Edge. 2 Share this post Link to post Share on other sites
mrtm2016 Report post Posted August 24, 2016 Thanks CB and Ravenrick96 for the detailed info. I'm having the same issue, sure is a pain for the pump and filter both to be in the actual gas tank. Share this post Link to post Share on other sites
