I have a 1998 F150 with 4.6 V8. 112,000 miles. 5 speed manual.
The motor shut off on the highway with no warning. No noises, no sputtering, no dash lights. Was able to coast over to berm. Motor would crank but wouldn’t start so I had it towed. When we arrived at the mechanic, truck started fine.
Mechanic had the truck for 2 days but was unable to duplicate the problem.
Checking the internet, seems to be 4 possible causes: fuel pump, ignition module, pickup coil or throttle body. Any other ideas? What's best way to trouble shoot this or do I just start replacing stuff?
Ignition module, pickup coil and fuel pump are original. Plugs & wires were replaced 2 months ago but the throttle body hasn’t been cleaned or inspected.
Thanks
Mark

 

So there are no OBD-II codes showing up with a scanner?

I would suspect a fuel supply issue and start with the pump itself, paying close attention to the wire harness connector.

You don't want to start replacing stuff because that gets expensive and often times never solves the problem anyway. It can't be overly complicated so I'd be looking closely for the DTC's----those will give you the best place to begin.

Hope its an easy and cheap fix!