You need to check the Haynes manual. My memory tells me that they have two types of FPRs. One type has the screws on top and the other one doesn't. When I was looking at mine which is a 86 I think the screws were on the bottom and nessecitated removing the fuel rail to get off. Luckily my problem that time turned out to be the MAP sensor.

 

fpr removal
-relieve the fuel system pressure
-pull fuel rail to access regulator screws, careful
-detach vacuum line from regulator
-remove three retaining screws from housing
-remove regulator gasket and o-ring
-check o-ring
-check gasket surfaces

 

No relay found there on the left fender/apron.

I was afraid I was going to have to pull the fuel rail. Guess I better make sure and have some injector seals available to replace the existing one. It never fails, If I don't have that kind of stuff readily available, I will destroy the existing one when trying to remove it.

My regulator is the type with the screws mounted to the underside. I can only get to one of them with the fuel rail in place. That figures...

Thanks for the help.
Still have never found the EEC relay. Found the Fuel pump relay.

 

i thought it was behind the the battery, looking at the haynes manual... for 1986 f-series pick-up electrical system, it shows EEC Relay, 4 wires, white/black (to ignition), black (to ground), red (to injectors/ecm), and yellow (to ecm and fuel pump relay) so i guess trace back the yellow wire on the fuel pump relay?

 

I'll take a look on that side. I know there are some vaccum solendoids on that side along with a bunch of other things. Maybe I'm just not digging far enough.

It would make sense. That is also where the code reader leads are located.

Thanks for the suggestions and technical assistance.

 

i don't look at mine that often, but i think there is a relay box behind the vacuum canister, check inside there, it is sometimes called eec power relay? the picture in my haynes shows the diagnostics port next to the relay box, but im not sure what year that is, also i think mine was laying free and not attached to the fender as pictured.

 

so i get home look at mine, haynes manual is off as normal, my 86 has the the coffee can style vacuum canister behind the battery, and behind it is about 4 plugs, and one attached to the side of the fender/engine bay... there is also a diagnostic port and an additional plug with nothing attached. they don't have any labels, and i don't have the box pictured in the haynes manual. maybe the one on the side is it?, it looks similar to the fp relay... but if that isn't it maybe it is in the cab somewhere? i looked behind the engine on the firewall, but nothing, i also have my airbox off, and mounting plate, but don't see anything but wiring connectors?

 

my 86 had the same thing going on replaced the TFI still would just shut off turned out to be the egr sensor have you checked the codes

 

O.k..... I thought I was getting somewhere with this thing, but apparently it was an illusion. The truck died again this morning. Started right backup. I'm still not getting any codes

 

I was just talking through this situation with a friend, who like me, has owned many Ford 1/2ton pickups from this era.

After discussing this situation with him for a while, we determined that the problem always seems to be occuring as the computer is changing from the warm-up mode to running mode. At or just above 170 degrees (That is the temp that Mitchell manual references). I wonder, and I was hoping somebody might be able to offer some insight, could this be an EEC module problem?

What might be some other symtoms to look for with a failing EEC?
I don't really want to replace this unless it is going to solve my problem. A new EEC with a 30 day warranty is about $130 plus a core charge. It also looks to be a paint to remove from under the dash.

By the way, I found the EEC relay last night. It is attatched to the EEC mounting bracket under the dash. Also kind of a pain to replace, especially when you add other electrical accessories and guages and decide to run most of your wiring across that area of the dash.

 

bump. bump.

 

Finally got the ECU to store some codes. The truck sat all night. Went for a spin after clearing the memory on the ECU. Note, the problem only happens during the first warmup cycle after sitting all night. Never happened during other driving sesssions during the day.

Driving down the highway at about 75 (3000 RPM +/-). The temp gauge read about 180 (w/ 180 deg Thermostat). The temp outside was in the mid 80's. Both temps are both higher than what was observed during all of the other stalls. All of a sudden, the tach bounced momentarily and when I stepped a little bit more on the accelerator, the tack dropped to 0. I immediately let off and the tach bounced back.

The two codes that were set in constant memory were 14 and 18.
14- Two or more successive erratic Profile Ignition Pickup pulses occurred, resulting in a possible engine miss or stall.
18- IDM circuit failure or SPOUT circuit grounded.

Obviously an ignition system problem. The TFI can probably be ruled out. I just replaced it this week with a new one. There was no change after the changeout.
I spent most of the afternoon checking the loom of wire that the ignition runs through. No notable conditions that would have caused the problem. I replaced some of the protective loom in an effort to protect the wires.

Also took the time to relocated the tach signal wire for my Sunpro tach. It was getting its signal from the coil primary. I moved it to the MSD tach signal port on my MSD ignition. By the way, I've already ruled out the MSD ignition box by eliminating it from the equation for several days. It resulted in no change in the problem.

If none of this fixes the problem, I'm thinking it may be the pickup coil in the distributor.

Any advice or thoughts would be helpful. Sorry for the long post.

 

Just an idea and hard to explan writing but if you don't find anything else......

I have found numerous times where wires "look" OK but have internal breaks. About the only way to find them is to pull on them fairly hard while while watching closely for any signs of stretching. Hard to say here how hard to pull as it is an experience type thing but I have found MANY wires like this. We nicknamed it the stretch test because it is so common.

Old 76 Pontiac 301 engines had this problem in the white magnetic picku p wire all the time. They were manufactured with the wire too short and after years of being pulled on as the vacuum advance yanked on it, the wire would break but it looked fine. A quick tug would show the wire stretching.

If you see anything like this on yours, while pulling on it, just nick the insulation with a razor or exacto knife and the whole thing will come apart since there is no wire holding it together. Basically, the wire is like a mini spark plug with the current jumping across the gap in the wire. Hit a bump just right and the gap gets too big to make it.

You may find something more simple but just something to keep in mind if all else fails. I just had another one of these last week on a Honda. Hours of wiggling wires finally pointed to the bad wire but couldn't find anything wrong with it. Stretch tested it and found a break by a tie down where it had been bent one too many times. Insulation looked fine but wire was broken inside.

Good Luck,

Lee

 

Thanks for the suggestion Lee.

I've been spending some more time checking the wiring. That seems to be the best explanation. The truck is 19 years old and most of the wiring under the hood looks like it.