Hey guys Im new here and seem to be having a issues with starting when sits for a long period of time . I bought a 94 4.0 v6 stepside in Dec of last year. It was neglected, but I managed to get a nice running truck after some work.
When I bought the truck the owner (friend of mine) put a new fuel pump in and sending unit. I did noticed a split in the fuel filler hose. We did a quick fix so I could get it home. The truck ran perfect up until I changed the fuel filler neck. It has a cold start problem. I have replaced the fuel filter, TPS, MAF, O2 sensors, and IAC all before the cold start problem.

When started in the morning it almost sounds like it's not getting enuff fuel, it runs really ruff for a few seconds and then dies. Start it again and the same thing, All while NOT stepping on the gas. Then maybe after 1 or 2 more starts it will stumble, spit and sputter and catch up and run good again. Runs fine all day. Till the next morning.

 

I was told to make my own post since I replied to another post with a similar issue. Soooo... in the last post I was also told it could be a vacuum leak or electrical issue. then the issue got worst and would run at all with or without the gas pedal and brake pedal was hard as a rock. Since then I have had it at 2 shops, one I didnt like because they told me it was my throttle body boot, and would cost $600, told them to shove it !!!!LOL. Then I took it to another old timer shop they did find a vacuum leak (brake booster check valve). It does start now but still have to give it gas for like 3-5 mins before it catches up and runs. Took it back to the shop and they cant find anything wrong. second vacuum check and fuel pressure checked out fine. They came up with maybe its carbon build up, after it sits for a period of time the carbon hardens and when starting the carbon soaks up the fuel preventing it from starting til it softens. (SCRATCHES HEAD) hmmmmm.

Any input????

 

Welcome to the forum

Cycle key on and off 3 times before starting
Key on, count to 2, key off, repeat 3 times

What you describe is classic symptom of fuel pressure draining away when vehicle sits for a few hours, overnight.

The computer only runs the fuel pump for 2 seconds with key on, its a safety thing
Your 1994 should run with 35psi pressure
2 second fuel pump run time adds about 10psi

Normally, with engine off, fuel pressure will hold for a few MONTHS, might drop to 20psi or so but no lower, so the 10psi tops it up for starting.

So try the key on and off thing to see if loss of fuel pressure might be the issue.
You can hear the fuel pump run for those 2 seconds, so make sure you HEAR IT, if it doesn't run EVERY time you turn on the key then could be Fuel Pump Relay is starting to fail, its in the engine bay fuse box, FP Relay

1994 uses a Fuel pressure regulator on the engine, it is behind alternator on lower intake on the 4.0l, it has the Fuel Return hose attached.
This is just a spring operated valve set for 40psi, if spring fails then system can't hold pressure, you can use a pair of vise grips and SOFTLY pinch the hose to close it off to see if system then holds pressure


Crank Position(CKP) sensor, NOT cam sensor, lol.
The computer isn't part of starter motor system, thats a separate system
So computer only knows you want to start the engine when it sees Pulses from CKP sensor, and those pulses also time the spark and injectors.
So failing crank sensor could cause no start until pulses were seen, but wouldn't cause startup and then stall.

My bet is loss of fuel pressure, fits the description down to a "T"

 

Thank you for the reply, I have cycled the key,and fuel pump does work.
doesnt work no matter how many times I do it I have also replaced the FPR twice. I have checked the fuel presssure and the shop did to. No loss of pressure.

 

Then do the 50/50 test
Pull off air tube to intake
Open throttle and spray gasoline or ether(quick start) into the intake
Try to start engine
If it fires right up then spark is OK but fuel injection was not
If still no start then spark is the issue

1994 uses EDIS-6 module for spark, it is located on rad support drivers side but on the FRONT side of rad support, at least on my 1994
EDIS modules rarely fail, I have read about vehicles involved in front end collisions that were rebuilt but EDIS module wasn't replaced, so.........just mentioning it.

EDIS module is self contained for spark
It is connected directly to the CKP sensor and the Coil pack.
It passes on CKP timing to computer for fuel injection, and gets back "vacuum advance" spark timing "suggestions" from the computer.


1994 computer will have 2 or 3 Blue capacitors on its circuit board that can leak over time and cause problems, like fuel injector pulses.
You do have to open up the computer to check for this.
This is a V8 computer but similar to your V6 model: http://support.moates.net/capacitor-...-ford-a9l-ecm/