No start(no fuel pump sound or CEL)

[ayyno]

Excuse me if this is a little vague or confusing, it's 3 am and I've been desperately searching to no avail, so I'm going to post it here.

I have a 1992 Eddie, and recently while driving it kind of half died for about half a second and was fine again, I was low on gas, but not empty(I've been lower) so I assumed I was running out of gas and as I pulled in the station it died and rolled it. Laughing about it thinking I ran out of gas we pushed it to the pump I put some gas in and went to start it...nothing.

I had no fuel pump sound, no check engine light. I assumed the fuel pump was bad...but I was able to jump the relay and it whines...so the fuel pump is good(thank god)

Now then I realized the CEL didn't come on when I turned the key at first...so I then figured it was the EEC relay...replaced that with a part from NAPA, didn't change anything. Using the paperclip method I was able to pull no trouble codes.

I'm worried that the EEC or "ECM" relay from NAPA doesn't have the same wiring or setup(can't think of the right terminology right now) as the relay I have, does anyone have a diagram or anything?


Any help is appreciated, if any more information is needed, obviously I'll give it to you. I just need to get this truck running again. I'm really hoping it's not a bad ECU.

 

[MrShorty]

I use the wiring diagrams in Chiltons, and find them to be adequate for the PCM power circuit. You can access an electronic version of Chiltons at Autozone's website (they require you to register to access the "vehicle repair guides").

These relays are pretty basic/pretty common 5 prong relays. I would not expect to get a "wrong" part in this case (though anything's possible). One thought, the PCM and fuel pump relays are basically the same. You verified that the fuel pump relay works -- swap it with the PCM relay and see if that clears up the PCM power problem.

 

[mgmgmg]

I had the same problem replaced the eec and fuel pump relays from napa fixed the problem 6 months later bingo same problem again!? Went to ford and bought the same relays problem fixed... that was 1 yr ago... just my 2 cents on after market relays same goes for thermo's... also when you replaced the relays put some elec contact spray in the replaced sockets..

 

[92exp4x4]

All the relays are the same part. You can interchange them with each other. This makes trouble shooting nice. I highly recommend using motorcraft parts especially when it comes to electronic stuff. If the EEC relay was bad you would have nothing - no pump, no start, just cranking.

Change the relays with good parts and start there. The EEC relay turns on the PCM and the PCM turns on the fuel pump relay to activate the pump.

 

[K5trailrunner]

just a quick question, have you checked the inerita (sp?) switch?? the one that is suppose to shut of the fuel pump if it is envolved in a crash. i have a 96 and my inerita switch is just above the carpet line in the passenger(right) foot well. they have a habbit of tripping after some time over small bumps, dips, hard stops, hard accelleration, and once tripped it is more offten to trip again easier than before. sorry if this dosn't help but it's a problem i've ran into quite often lately
GL anyhow hope you get it soon

 

[ayyno]

Yes, the inertia switch is good, I checked it.

Also, the that's what I get, just cranking, although I have a push button wired to my starter due to a bad wire or ignition switch or something, could that affect it? Also my turn signal/reverse light/rear defroster fuse keeps blowing when I put it into reverse, and it rarely has the 3-4 shift, but good TC lock up, anything that could be the same problem here?

When I am in the KOEO(key on engine off) posistion, no check engine light flashes, which is why I'm thinking it's the EEC relay, it just worries me that the original is 4 prongs, but all the replacements are 5 prongs.

 

[FIND]

I would start with checking out that wiring for your ignition switch and the push button start, and if possible, taking that back to something resembling stock. If I were a betting man, that is where I would put money that your problem is at.

Don't worry about the 4 prong 5 prong difference... the function of the prongs that you will be using are no different, the 5th prong is just there to make it more universal. Some applications use that 5th prong. Having it there won't make any difference though because it won't be in contact with any of the wiring.

 

[ayyno]

Well the push button start is between the battery and the starter solenoid only because somewhere along the line that failed, now I don't know whether to replace the ignition switch(under the steering wheel) or the ignition cylinder(actual key) and hope that it fixes my problem. I'm still gonna look into the EEC relay tomorrow.

 

[ayyno]

EEC relay is good, I can hear and feel it engaging...however, fuel pump relay is not...can't hear it or feel it. HELP

 

[Robert Nick]

Also, the that's what I get, just cranking, although I have a push button wired to my starter due to a bad wire or ignition switch or something, could that affect it? Also my turn signal/reverse light/rear defroster fuse keeps blowing when I put it into reverse, and it rarely has the 3-4 shift, but good TC lock up, anything that could be the same problem here?

I would also repair the short circuit in the above paragraph. In place of the fuse insert a 1157 Lamp with both filaments tied together. This acts like a short detector. The Lamp will be full bright when the short is present. When it is fully illuminated the loads on the circuit such as the Reverse Lamp Circuit, Turn Signals, Rear Defrost Grid, etc. can be individually unplugged. If the lamp goes out or becomes dim you have found the suspect branch circuit. I had the same problem on Gen1 about five years ago. The issue was in the Transmission Valve Body. Unplugging the Harness going to the Transmission turned the Short Detector Off. Repaired the Valve Body Solenoid. Good Luck.

 

[ayyno]

I need a diagram of a relay...cause the relay I got from napa and now advanced auto has a coil between 1 and 2, 4 going to idk(ground maybe?) and 3 and 5 being the switch.

This brings the problem up of 5 on the relay is going to an empty slot...I need a relay that goes between 3 and 4 with a coil between 1 and 2.

Sorry if my terminology is incorrect and it's hard to understand. I'm using the slot numbers for wires by the way.

 

[ayyno]

Okay, so if my EEC relay is clicking and working, but my fuel pump relay is not...and neither are the replacements...why do I have no check engine light when the key is turned? Bad ECU?

PS...it's extremely windy and cold here in NJ right now...I miss having a garage.

 

[FEAR30X]

Okay, so if my EEC relay is clicking and working, but my fuel pump relay is not...and neither are the replacements...why do I have no check engine light when the key is turned? Bad ECU?

PS...it's extremely windy and cold here in NJ right now...I miss having a garage.

and it says its 30f outside right now, im north of you

 

[ayyno]

Let me rephrase...cold and extremely windy, 20-28 mph winds make it feel like 18f.

I'm a little frustrated between the truck and the wind beating my face in

 

[ayyno]

Well, unfortunately with my work schedule, I don't have time to get her up and running again...I will let you guys know what was. I have to take it to a shop

 

[DV8]

i dunno if the x has it, but i had a 93 sherman tank (aka ford tempo) i bought for $85 that had the same problem, but you could thump the fender with your fist (typical redneck repair method) and the CEL would come on, the fuel pump relay would click, and the pump would prime the system. after about 2 years of this, i figured out by accident that it was the BCM (body control module.) i drove it like this for another year, then it got to where i had to beat it with a hammer to get it to work. replaced it, drove it another 3 years no problems. also, the FP relay was integrated into the BCM. oh, and i sold it for $800 after driving it for 6 years.

 

[ayyno]

I tried hitting and shaking, hoping I could bring two contacts together that maybe weren't getting contact, but no no avail. The Fuel Pump relay and EEC relay were both good, but the fuel pump relay seemed to be getting no power.

 

[jason's 94]

try testing to see how much voltage is or isn't at the pump. check for resistance in the between the pump hot wire and the relay. check to make sure the pump ground has a good ground.

 

[92exp4x4]

Chances are then your PCM could be bad.

When the EEC relay closes, it sends power to the PCM and the pump relay coil, if I remember right. The PCM will give the coil its ground and operate the relay, in turn operating the pump. If you have voltage to the pump relay coil follow the neg side of the coil and see if you still have voltage. Eventually you will get to the PCM. If you have voltage here and no pump operation with the key on, then the PCM is most likely to be at fault. If the pump was to run the voltage would drop to near 0 on this circut.

The first gen explorer only has a Powertrain Control Module. Other features are controlled independently. They do not the body control module previously mentioned.

 

[ayyno]

I need to get out there with a meter and check for voltage...maybe it was a sign that I wasn't able to get it to the shop today...hmmm

Anyway, could the PCM just go out while driving like it did?