Does the E 350 van have a cabin filter? The AC seems to be blowing some through the defroster but none thru the vents.

I guess no answer means no cabin filter.

This is more likely to be a vacuum leak issue. There are vacuum operated valves that control where the air blows. Ford calls these valves "vacuum motors". One of them may have failed or one of the vacuum lines going to them may be leaking.

I had one of these last night. Same vehicle same concern. I found the vacuum line for the AC/heater controls had been eaten by rodents. Since Ford decided to use plastic tubes (this one's red in color with a black plastic conduit) the lines become more fragile over time. Pull the air filter, snorkel and housing and look on top of the right side of the motor. It's a solitary vacuum line that goes from the back of the engine to the top of the heater case. If this line is in tact, the vacuum reservoir and or check valve may be faulty.

P.S. - With a full time job as a mechanic working swing shifts, I and many of my fellow technicians can't get to this site to answer questions until we get home and have dome down time. Also - we do this work all day, sometimes in our off time and usually while we sleep! Please be patient with us - it's out time and expertise - voluntarily.

You might want to take a look at the evaporator coil. If it clogged with dirt and lint it will cut down on the amount of air you get in the cabin of the van.

where is the CABIN air filter on a ford e 150 /2002 >>?

It seems that your vacuum motor is not functioning if you have a Ford van you can pull off the cover on the dashboard and manually push the lever on the back your motor in the word this will allow air to come out of the vents

Hmmm similar question does my 2000 e450 have a cabin filter, apparently no. Trying to figure out how to best eliminate smoker odor apparently coming from AC..

The vacuum motor answer was very helpful PS.

My ‘06 E250 does something similar. But here’s the kicker... if I tap the brake, the air starts blowing again. If I go uphill, it stops—unless I brake— and starts back up when the van goes downhill. But, every time I hit the brake, the air starts blowing again. People must think I’m crazy, braking for no reason. lol

you are not crazy. my 04 doing same. CANT GET TO FORD VAC RESERVOIR , so rig a new vacuum reservoir and check valve under dash to vent lever. should solve problem. check valve YG193 RESERVOIR YC2Z- 19A-566-AA FOR MY 2004 E350 5.4 L .