HI have a 1987 Ford Bronco 2 a 2.9L vehicle ideles normal when driving around 45 mph engines bogs down sputters then picks up. Also as go up incline engine looses power. I have changed distribitor, rotor button, plugs and wires, What's my next course of action?

Overdrive is used for fuel economy. Normally, the highest gear on a vehicle has the engine-to-transmission ratio at 1:1, meaning for each revolution of the engine, you get one revolution of the driveshaft. This normally provides best fuel economy. To improve on this, overdrive actually gears even higher than 1:1, meaning that you get a bit more than one revolution of the driveshaft for each revolution of the engine. This can improve fuel mileage, but also has risks - the engine can easily bog down under heavier load conditions or on inclines. Most vehicles that used O/D, one you shift into it, use it when the engine load allows for it, and will automatically shift down to the normal Drive range when needed.

Wiggle the engine harness and see if the engine dies, do this everywhere that the harness has allot strain on it due to engine movement.

I am guessing its your TFI or Thick Film Ignition module. Usually located on the underside of your distributor, its either grey or black in color and often when it is going bad it acts like this: Usually starts fine, runs ok for about 20 min then engine dies. cranking engine sounds normal but no start. checking spark will have no sparks. Leave hood up and allow to cool (also TFI very hot to the touch) I packed Ice around it once (in a ziplock) that made it run in about 45 min. NOTE: get ready to replace real soon because its on the way to breaking down.

I am going to assume this is a full size Bronco with a 4.9 or 5.0 engine.
The computer controls the idle speed by the amount of air allowed into the intake thru the idle air control valve.
If the throttle body is dirty or the valve fails, or if you have a serious vac leak, the engine RPM will be higher than normal.

sounds like the ignition module is going bad.

brake hose could be bad or this is normal for engine to brake vehicle all autos do this it is called engine braking it is normal. if your brakes are wearing uneven then i would suggest a brake hose on the passenger side.

most likely the fuel pressure is just low enough to run but sputter on an incline

sounds like catalytic converter to me




james ray

you will need tocheck choke/choke pull off also the egr could be malfunctioning

The idle air control solenoid could be bad. give the engine a vacuum leak and see if that helps any