Solved the sudden death problem

[gsmaclean]

Out of nowhere, my 94 Limited died on me a few weeks ago. It was running fine, I pulled into a store, 5 minutes later I came out, put the key in to start, cranked it - and nothing. I cranked it again, hoofed the gas, and it ALMOST caught - stumbled, then quit again, exactly as if I had run out of gas.

It was very hot outside, 95F+, so I figured, "heat related." I sat there for the next 5 minutes or so, cranking it every minute. Nothing, not the slightest hint of catching.

Then, the next time - it starts up perfectly as if nothing was ever wrong. I figured it was a fluke, and let it go.

Then it happened again a week later. And again a few days after that.

I went away for a week, and when I came back, I went to start it - and it would have nothing of it. It would not come back to life this time.

I hooked up my code reader, and it reported "fuel pump secondary circuit failure." hmmm. I turned the ignition on and listened for the fuel pump. Nothing. That would explain the "running out of gas" symptom.

I opened the relay box and put my finger on the fuel pump relay while turning the ignition on. I felt it click. Strange. I pulled the relay out and jumpered the contacts with a piece of wire. The pump ran. I turned the ignition on, the truck started.

I put the relay back in, turned the ignition on, relay clicked, no fuel pump. OK, bad relay. I pulled a relay from some other non-critical circuit and plugged it into the fuel pump relay position. Turned the ignition on. No fuel pump.

OK...I pulled the relay out and wiggled it while turning the ignition on. Fuel pump came on intermittently.

So I took some contact cleaner (actually, I used brake cleaner, too lazy to go downstairs and get contact cleaner, and it's essentially the same stuff) and hosed down the relay socket. Once it dried, I plugged the original relay back in - and hey presto, it all works perfectly.

Obviously it was just a bad electrical connection on the fuel pump relay secondary circuit in the socket. An easy fix, not so easy diagnosis. I figured I'd post it here, in case anyone else came across the same problem.

 

[410Fortune]

VERY COMMON PROBLEM ON ALL FORD RANGER BASED TRUCKS when they get older

thanks for sharing!

 

[BigBlue94]

relay problem

Thanks a bunch, i am having this very same problem, even had one time while driving that it just stopped dead like I was out of gas. Then a minute later it fired right up. I will give this a try. Makes driving an adventure!

 

[BigBlue94]

where is the relay

okay, so where is the fuel pump relay? I looked it up in my Chilton manual but do not find a listing for "Fuel Pump Relay" Checked the fuse block under the dash and the diagram does not show a relay there for the fuel pump.
Under the hood?

 

[MrWizard]

Under the hood. Six relays in a rectangular black box on the passenger
side in a '94. For the fuel pump, heater blower, ABS, etc.
If the fuel pump relay won't un-stick you can swap it with a less critical
one next to it, like the heater blower relay or A/C WOT relay, until
you can buy a replacement. They are all the same part number.

okay, so where is the fuel pump relay? I looked it up in my Chilton manual but do not find a listing for "Fuel Pump Relay" Checked the fuse block under the dash and the diagram does not show a relay there for the fuel pump.
Under the hood?

 

[Freshmeat]

This is also a very common problem among the Crown Victoria / Grand Marquis / Town Car chassis. Same fix- find the fuel pump relay, spray it down with contact cleaner, and rock out.

 

[BigBlue94]

problem continues, but....

Okay so the problem keeps going. its been weeks since the sudden no start problem. you can see previous threads about this. The good news i have pin pointed the problem to the power distrabution box(the black rectangle box under the hood) i replaced the fuel pump relay switch and went several weeks with no problems. Then as usual out of the blue after going into a store i came out and it would not start....just the usual engine cranking over. I left the key on and opend the hood and gave one solid smack to the box. Right away i could then hear the fuel pump do its 3 second cycling/pressurizing and then it started right up. i went the rest of the day in and out of the car with no problem. the next day the very same thing happend again. one single knock to the box and bingo on goes the fuel pump and then i can start the car. as i said i have replaced the relay for the fuel pump and the contact area does not look corroded. What should i do since the problem seems to be from this box??
Thanks for the help

 

[MrShorty]

Mine did something similar. One time when it wouldn't start, I got under the hood with a voltmeter. Found I had power to the fuse, power through the fuse, but nothing to the relay. Suggested to me a loose connection somewhere between the fuse and the relay. Repeated a few times to confirm, then cut the old wire out and put a new wire in between the fuse and the relay and all was well.

With this, I'm not advocating re-wiring the fuel pump circuit. I would suggest getting a voltmeter and wiring diagram and, next time it won't start, instead of thumping the box, see if you can open it up without waking up the fuel pump and determine where the circuit appears broken.

 

[jdawg99]

I have been experiencing the same problem as gsmaclean and bigblue94. I have also bought a new relay and switched it out, sprayed out the relay contacts with cleaner. I have bought the new fuel pump, strainer, and plan on new fuel filter. I like what this forum brings to the diy people out there. I have been given the different aspect of diagnosing problems that other people are going thru. Just got done swapping the trans and front brakes on my explorer and finishing up on a total clutch job on my '90 F150. Thank you all for some great info. I will report on anything else I can help with.

 

[Nick26]

Could this problem apply to a 98 too? everyone who commented was a 1st gen. I don't see a second fuel pump relay in my owners manual...

 

[TedJ]

See if it's not the EEC relay doing the same thing, is the CEL on when it won't start (indicating EEC power)?

My parts truck does this sometimes when I try to start it (it dosen't get driven) I smack the box or wiggle the relay, and it works, Mine is the EEC relay because the CEL does not come on when the key is in the on position. I swapped the A/C WOT relay for the EEC one, but it didn't make a difference.

I suppose it could be the same in a 98, at the least it HAS to have some kind of fuel pump relay, even if its not the problem.

 

[fordktpjoe]

Heya folks! sorry to dredge up such an old post, (nearly a month) but as an earlier poster said, it is a common occurance on the crown vic/grand marquis models too.

Had a similar problem on a '90 vic, ran fine fall thru spring, (cool to cold temps) but come hot weather, 80 or above, drive it on a fairly long trip, say 50 miles or more, and it'd just shut off, just like you turned off the key. Let 'er sit 5 minutes, She'd get ya a mile or so down the road, and quit again. Let 'er sit 20 minutes or more (a good long cool down) and she'd getcha on home.

Shot the F/P relay contacts with a lil' PB Blaster, replaced the relay just for good measure, (it WAS 20 years old after all) cleared it right up!

 

[boggs1227]

my 2 cents....... after knowing that the relays can be a problem .had anyone thought about the "keepers" that the relay fits into being a problem ? reason i say this is that i have cars in the past with somewhat similar problems and when a new relay wont fix it i just swapped the keeper or made sure it was makeing good contact up underneith when it got fit into place .

 

[slayer]

Just a quick comment to add to the fuel pump relay problem i have a 94 xlt with the same ploblem. But almost all the relays was loosing contact i tryed the contact cleaner but no change. I tryed a to bend the relay terminals so it would make better contact. It helped for a while but it went back to the same thing i finally got so tired of the not starting or the heater blower not working that i replaced all the terminals in the relay box no problems since the stay con's were realy soft so i hope that saves you some of my former headaches

 

[smegun]

87 VS. 87A seems only one spot utilizes the 87a optional ground tacky relays beat em on the desk a little they free up anyone have a skematic of the power distribution box wiring itself

I am curiouse why I have intermittent probs also with fuel pump not coming on should we add clean grounds to negative on these since the truck is increasing in ohms over the years and getting out of spec 1 ohm for every foot of wire that may be problem

current dissipating to wrong location