94 Brand F Engine

[HWestfall]

My son has a 94 Ford F-250 4WD Power Stroke. #@$%!After it gets up to full Operating Temp. it cuts out like the ignition if turned off,:{ then right back on. Even at Freeway Speed it jurks of you let off the throttle. Sometimes at stop lights it dies. But it starts right back up. Oo. What would cause is? Harry Westfall



02 3500 HO, Pat. Blue 4x4 6 sp Laramie, Chrome Bush Guard w/ 4 KC Dayliters, Triple Isspro Gauges, DeeZee running Boards,Stainless Side Panels & Wheel Well Trim, Panels,Sprayin Bed Liner, AFE Stage 1,

 

[bmoeller]

Cam sensors are a common problem. IIRC, it takes a 10m wrench and small pry bar. Best to keep a spare under the seat.

Also, some of the early engines were prone to having the grommets that pass through under the valve covers rubbing through.

If those aren't it, you might want to check the pressure output of the high pressure oil pump (HPOP). That pump creates the pressure needed for the HEUI injectors.

 

[Wingate]

Isn't the 94 is a low pressure engine. I don't think the 94 is a HUEI. My Father-n-law has a 94, its a 7. 3L n/a engine with a standadyne injection pump.

Either way, I would suggest changing the fuel filter first. I found that on my in-laws truck, the water seperator plate that screws to the bottom of the filter was sucking air at the drain screw. If left sitting for 24hrs, it would start for a few seconds, then die and have to be bled out to run.

If its dying but will restart, could be fuel filter or low fuel pressure.

If this is the older low pressure standadyne injection system, it could be the fuel shutoff solenoid on the back of the fuel system. I can't remember if these solenoids are latching or not, you can determine that by starting the engine, and checking the fuel solenoid wiring for 12v power. If it has power applied after starting, it is not a latching type solenoid.

My bro-n-law has a 97 that is a Powerstroke with the Huei fuel system that just recently started the same symptoms you described. He had already installed a new fuel filter and the truck was still acting up, I had him pour a qt. of two -stroke oil in the front tank, another qt. in the rear tank and fill both tanks up. The truck made it home from the trip he was on (approx. 250 miles away while towing 4 horses) and had no futher problems once the two-stroke oil got into the engine. I haven't actually diagonosed the problem yet but being that the two-stroke oil fixed it, I would venture to say that the injectors are hanging up.

Different versions of the 7. 3l engine have ENTIRELY different fuel systems and require different approaches to troubleshoot/repair...

Good Luck.

 

[bmoeller]

The PSD came out in late '94. It could be either engine. They don't look anything alike, so not hard to tell them apart.

The fuel supply pump could be it as well. IIRC, it is an electric fuel supply pump. Also, i remember there being a mercury switch that could go bad. It is there in case of rollover.