I have a B250 5.9L van, 1985. It runs rough at idle, and burns rich. Any ideas. I put new distributor cap, and wires the plugs were good. When I turn the air conditioning on it almost stalls.

thanks, Dave

 

Is it throwing any codes? Do the key 3X dance and count the flashes.

Are the O2 sensors the original ones? When was the CAT replaced? Is the CAT clogged?

 

stev, it is a 1985. No computer, no 02 sensor.

Replace the plugs, and make sure you did not cross any wires when you changed them. I recently knocked one wire loose on the dist cap and could not even tell with the engine idling. I forget which cylinder it was, but I knew something was up by the exhaust smell, then I heard the ticking when I looked at the dist cap.

Put a timing light on the harmonic balancer and make sure it is within 5 degrees of what the sticker under your hood says

 

High mileage? If so, the timing chain set could be worn.