Heater will not shut completely off

May 06, 2006 Last reply: 20 years ago 3 Replies
Jump to replies (3)
2000 Ford 350 V10 RV. The heater will not shut completely off. Most noticable when climbing hills and more heat generated.

Is there an easy fix other than installing a valve on the heater hose?



Thanks,



Dennis


Sounds like you may have a vacuum leak. When climbing hills vacuum will drop even more. How about A/C? Does the air duct flip from front vents to the defrost or heater vents when accelerating or climbing hills?

Yes. Where is the most common location of a vacuum leak?

I'm not sure. Any vacuum line around the battery would be suspect. Corrosion from the battery quickly deteriorates lines running nearby. I know on Dodge trucks the cruise control module is mounted under the battery and the vacuum line running to it is very common to leak. I'll have to take a look and see what might be a common place to look on a Ford.

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required