1986 Ford Bronco running rough

[86reaper]

I have an 86 bronco with a 88 bronco engine in it, the truck is running extremely rough and we have replaced the spark plugs, wires, starter soleiond, and the ignition control module. the truck still ran rough, so we took off one of the O2 sensors and it ran decent or better, so yesterday we put a new O2 senor on it and it ran worse than it did before. I need advice on this

One person is telling me i should take both O2 sensors off and plug those holes and then turn down the fuel pressure and trick the computer into burning the gas leaner. Is this a good idea or does anyone else have more insight on this issue that i am experiencing

 

[Spitfire1975]

pull codes. Could be a combination of sensors reading wrong. I wouldn't try to "trick" a computer. Just asking for problems.

Sensors that could be throwing things off:
Coolant Temperature Sensor
Air Temperature Sensor
EGR Components
O2 Sensor (my 86 only has one)
IAC module
Throttle Position Sensor
Knock Sensor (probably not your issue, but the computer does read it)
TFI (Ignition Control Module)
MAP Sensor

You could also have a weak coil or bad/going bad distributor Stator/pickup.

Check your compression and vacuum. Fuel Filter been changed recently?? What is the Fuel Pressure?

Start by PULLING CODES. Look in the tech section. There is a page that will show you how.

 

[86reaper]

Thanks bro, while i was at work yesterday the tech told me he wanted me to get a coolant temperature sensor, so im guessing hes on the right path, but to day when i get off im going to get him all of what you said im going to start off with the coolant sensor, the air sensor, and the throttle sensor, i guess next week ill get the map sensor, erg sensors, and a new coil if he says it needs it, What is an IAC Module im dont know what that is thanks for all your help bro ill let you know how the build is going

 

[Spitfire1975]

it is the Idle Air Control and sits on the passenger side of the Upper air intake (plenum). Usually they just need to be cleaned out real well.

 

[b2rich]

my 87 B2 was running good. but it did have some hesitation and low power. I used about 3/4 can of seafoam in the gas. with in about 40 miles i noticed a big difference in the performance and the idle. runs even better now. I did not go thru the vacuum line.
just a thought. you might want to try it.