A/C blower switched from panel to defrost during acceleration
The airflow is switched from panel to
defrost during acceleration. The airflow
switches back when I let off the accelerator.
Had anyone else experienced this and have
Check for vacum leaks.
And again we agree
There's a check valve in the vacuum system. Either in the vacuum line coming from the intake manifold to the control panel on the dash or, if this is an automatic system, it may be inside the programmer. When you accelerate intake manifold vacuum drops off. That's why it is switching. The check valve's job is to hold the vacuum level in the system under acceleration. HTH. -Jim
Looking for a Used F-250 Super Duty in your area?
CarGurus has 43,935 nationwide F-250 Super Duty listings starting at $2,400.
Search Ford F-250 Super Duty Questions
Ford F-250 Super Duty Experts
Related Models For Sale
Used Cars For Sale