jtmh37

I'm a new member to this forum but have been following threads for a while in an attempt to troubleshoot issues with my F150. If anyone can help, I would greatly appreciate it.

Truck:
1993 Ford F150 2WD
351w EFI

Symptoms:
Starts right up.
Stalls abruptly after 20-30 seconds.
Sputters when trying to restart. Will eventually start and die after 1-2 seconds.
Will start and keep running if I hold the ignition key in starting position.

Things I've tried:
New inline fuel filter.
New Fuel Pressure Regulator.
New plugs, wires, cap and rotor.
New coil.

does anyone have a suggested solution?

93Cobra#2771

iTrader: (2)

Does it do this off both fuel tanks?

jtmh37

It does this off both tanks.
The stalling is very systematic, repeating the same cut and sputter routine every time.
It smells flooded after about 1-2 minutes of trying to start, and then will not start again unless I leave it sit for 4-5 hours. Then it repeats the routine: start, sharp stall, start & sputter, no start.
Haven't tested fuel pressure, but it appears to have good pressure on the rail, and I hear the pump initialize when I turn the key on, before starting.
In crawling around, it looks like the O2 sensor is bad (broken wire).
Also, I had a guy tell me that he thinks the starter might have been going bad before this began, because when starting it warm, the engine would not crank very fast. Sounded like a drain on the battery. Not so when starting cold.
Would either of those cause the stall/no start scenario?

Watt-maker

You need to see if the truck is losing spark. I'm guessing the ignition module off the side of the distributor. I would also check the fuel pressure just to make sure it's not that.

93Cobra#2771

iTrader: (2)

Still need to check cranking fuel pressure. Also need to verify you are getting good spark.

Broken o2 wire isn't an issue during cranking, as it isn't used for first 90 seconds or so of running.

Could have a leaky injector or could have bad spark plug or wire or coil.

When it floods out on you, try holding the gas pedal to the floor and then cranking. EEC won't send fuel but will sen spark. It will clear the cylinders and mane even fire off pretty good.

There are specific tests to check the coil, wires, ignition module, etc. I highly recommend getting a chilton or Hayes manual and start studying as opposed to throwing parts at it.

jtmh37

Thanks for the posts! I've been researching the Ignition Control Module and Pickup Coil symptoms online. Unfortunately, my knowledge is limited on anything newer than a 1980.

If anyone else has a possible solution, I would appreciate it.

Thanks again, Cobra.