Questions and Answers

Ford Probe Heater Problem Q. Vince, I own a 1996 Ford Probe GT, 2.5 liter 24 valve engine. My problem is in the heater. When turned on, the air blows through the window defroster and will not switch to vent, floor or mix positions. I have removed the paneling and found color coded vacuum hoses leading to the actuators for each air position.

It appears the black hose should be the source hose. This black hose runs from the air position switch to heater/blower and disappears. I have disconnected this hose, ran the heater, but do not feel any vacuum on the hose (put my thumb over the hose).

Am I correct in thinking this black hose should have vacuum? Should I remove the heater box and continue to trace this hose? Or, can you tell me where the vacuum source can be found? And how to correct my heater problem.

Of interest, I recently had my local Ford dealership repair an oil leak in by valve covers (oil leaking into around the spark plugs). I'm not sure, but believe the heater problem came about after the repair. In other words, I have not had a reason to use the heater/AC until now and discovered the problem.

Thank you,
Olin

A. I would look under the hood for a disconnected vacuum line. In replacing the valve cover gaskets it is very possible that it was missed and not reconnected. It is a small line and the resulting vacuum leak really wouldn't affect the engine so you'd notice.