No Start issues

[fordexplorerLA]

Here is my situation. I have a 95 Explorere XLT with lots of miles!
I have been having issues with a no start for a few weeks now and I went ahead and replaced the fuel filter. It ran good for a while and then it finally died. It cranks but doesn't seem to have any fuel. I have been reading threads about inertia switch/fuel pump - relay, fuse/ and something in regards to PCM(?). The relay (if I have the correct one) appears to be clicking when you switch the KEY ON. There are actually 3 relays in the vicinity and they all appear to be clicking ON/OFF when the key is turned ON.
I have tried swapping two relays that have identical part numbers, but no sigar. I do not hear the "buzz" sound coming from the fuel pump. I have checked voltages at the inertia switch and fuel pump connector. I will get about 11.45 V for a few seconds when KEY is turned ON and then it drops to about 9.5 V. It seems to be at both locations. At this point, I am guessing to be the actual fuel pump itself, but before I went ahead and took the tank down, I wanted to get any last efforts out of the way and see if I can make certain it is the pump and not a connector/fuse/relay.
Any ideas/pictures/drawings are welcomed! I'll be working on the truck this afternoon and see what I can find. Thanks for the anticipated feedback.

 

[JDraper]

If you have voltage at the pump, and you still have no fuel pressure with no whine from the pump when the key is turned on..it's time for a new pump. Hopefully you don't have too much gas in the tank. It's a pita to lower it when it's full...Have fun

 

[fordexplorerLA]

I think I have voltage at the pump. I have four wires at the connector. Basically two are ground and the other two are signals. I believe one is for the fuel pump and the other for the sender(?-I might be wrong). On one of the wires when I turn the key to ON, I get about 11.5 volts (constant). While the other (believed to be for fuel pump) I will get 11.4 volts for a brief second and then drop down to about 9.5 volts. If these values sound correct, then I might have a bad pump. Any other great ideas would be great.

Thanks!

 

[RICH JELINEK]

Check Engine Lite Flashes Same As Fuel Pump Relay Clicks???

I've got a similar situation with our 1997 explorer, 4.0 SOHC.

Quit running on us yesterday, had to trailer it home. It will start and run for a second or two, then dies. When we got it home, about 2 hrs from when it broke down, it started right up and ran just long enough to back it off the trailer, then died again. Has spark while cranking, can hear fuel pump running for two seconds or so when turning key on. Put a fuel pressure gauge on the rail, and it does take a few cycles to get the pressure up to about 40 psi. Each cycling of the key gives it about 10 more psi - 10, 20, 30, 40. If I cycle the key like this a few times it will start up, runs for a few seconds and dies like it runs out of fuel.

Here is where it gets interesting, and I hope someone can explain this part;

When it starts up and dies, key still on, the check engine lite flashes pretty quickly and the fuel pump relay clicks along with the flashes, and before I had the fuel press. guage on the shrader valve I noticed that fuel pulses ( as I hold the schrader pin down with a small punch ) with the clicking relay/flashing lite.

Now if you try to start it again WITHOUT turning the key off, it will not start.

Turn the key off, then on again and it will start for a quick second and die, like it runs out of fuel.

Also if I pull the PCM relay, that will stop the fuel pump relay from clicking and the lite from flashing, but I guess that makes sense since that is like turning off power to the PCM, correct???

Also, when the CEL is flashing, it seems dim, like only half as bright as normal. Turn the key off and back on and the CEL is full bright.

The truck did this same deal about 2 1/2 weeks ago, and in the middle of trying to diagnose it, the problem suddenly disappeared and it has run fine since, until yesterday and now the problem is back.

Two pros have told me it is the fuel pump, but I just want to be sure before I spend the money and drop the tank to find out that was not the problem. The flashing CEL and clicking relay is what is confusing me making me think it is something else, like possibly the PCM ITSELF???

And BTW, there are NO trouble codes stored, although I am only using my Superchips Programmer from my PSD to check for diagnostic trouble codes, but I don't think that would matter?.

I also tried swapping the relays around and that didn't make any difference.

Anyone have any ideas - should I just put a fuel pump in it, or do you think it's something else???

I need to fix this thing before the problem dissappears again, it's impossible to fix it when it's not acting up, but we don't want to drive it until I find something solid so we can trust it again.

Sorry this got so long, and I didn't mean to hi-jack this thread from fordexplorerLA, but it sounds like we have similar problems.

Any help is greatly appreciated!!!

 

[marragtop]

To FORDEXPLORERla: with the key turned on, try rapping on the gas tank with a rubber mallet. This may cause the pump to kick on momentarily. If so, you need to replace the pump.

 

[fordexplorerLA]

Problem solved!

FYI - We finally fixed the problem last weekend. We decided to take the tank down and replace the fuel pump (no buzz when key turned). I went through the complete circuit of the fuel pump from the initial turn of the KEY to ON position. I checked the voltage at every location, starting from the relay to the inertia switch back down the the connector to the fuel pump! All showed around 11.4 volts momentairly (1-2 secs) and then dropped down to about 9.5volts. Before pulling the tank down, I unplugged the old connector, carefully pluged in the NEW pump and turned the KEY to ON and we got the pump to run! After replacing the pump, the truck turned on with no problems. Has been running for over a week and no sudden start-up issues. I hope this helps, you (RICH JELINEK) may be experiencing other issues along the way. I also replaced the fuel filter before the pump which appeared to work for about a week when it completely died. I am not sure why you see the flashing of the CEL light. You can tackle the fuel filter which may be preventing the gas to reach the engine and giving you low pressure. That would be the easier job of the two, if it doesn't fix you problem, then spend the money and replace the fuel pump assembly.

Good luck!

 

[RICH JELINEK]

Thanks for the info, LA, I picked up a pump and a new filter ( even though the filter on it is only about 6 mos. old ) on the way home today so I'm going to try a few other simpler things and then drop the tank. Someone else here suggested for what they cost try replacing both the fuel pump AND the PCM relays first, so just for the heck of it I'll try that first.

Thanks again,