loss of power while driving

[74bronco302]

i just bought my 74 bronco 2 weeks ago and everthing has been working properly until a couple days ago. first time it happened to me i was at a stop light low on gas in main so i switched to aux. drove off fine but a minute later there was no response in the gas pedal and the car slowed down but engine was still running. i went to the side of the road. this was on a highway going about 60. i sat there and rolled along side of the road until i felt i got the power back and gassed it and got back on the road. then i drove home the rest of the way fine. next time i was driving to work in the morning and i was doing 60 and the power all of a sudden dropped off again. i can kind of gas it and it might go for a second but it still ends up on the side of the road coasting. the rest of the day was fine after i creeped into the parkinglot. then today driving to work it happened to me in the same exact spot but only lasted a couple of minutes. the last episode lasted about 15. it drives perfectly 98 percent of the time but it has that speratic power loss. its been happening when i am about to start up a big hill . but i dont think thats the problem cause i take bigger ones the trip and it has no problems. its a 4 year old engine with 20.000 on it its a 302 and starts of fine. some mornings better than others. i cleaned the fuel filter last night after the second episode then today it happened again but not as bad. its like a total power loss though. this problem doesnt make sense cause the car runs perfectly at idle and on the road. it just has random power loss. if you have any ideas id appreciat that. thanks

 

[Bully Bob]

You didn't mention..... is it doing this on both tanks now, .....or just the aux...?

If it's the aux. tank, then there's your prob.

Could be a plugged/colapsed fuel line.

Could be a "mucked-up" tank & the pick-up tube is sucking stuff in & then droping it when the eng. slows, or stops.

Could be the tank switch-over valve is plugged.

Or, it could be "Murphys Law"....& the fuel pump went south at the same time.

 

[MBell70]

My want to check your ignition coil. When the ignition coil starts going bad and when it gets hot it some times becomes sparatic. Also replace spark plug wires if they are old. One other thing is that your engine is vapor locking. The fuel in the carburatot is evaporating from the heat of the engine. Solution is to add a resin spacer between the carb and intake manifold. Good Luck