Q: Airflow changes when I step on gas pedal

asked by on February 08, 2016

When I accelerate, the airflow goes from the dash vents to the defroster. When I let off the gas, it returns to the dash vents.

The AC has a vacuum reservoir that is designed to hold a vacuum to the AC blend doors during acceleration, or low engine vacuum conditions. If this system is leaking, the system cannot hold vacuum to the AC, and will default to the defroster vent when vacuum levels drop. I recommend that you have a mechanic, like one from YourMechanic, check for broken vacuum lines, or a leaking reservoir, through an inspection of your entire AC system.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

i just brought an new alternator for my car a couple days ago and had it put on then somehow when i crank the the car the battery

The battery should be load tested to determine if it is usable. A degraded battery, or one with an internal short, will cause charging system problems. If the battery only marginally passes the load test, replace it outright to reduce...

Air conditioning is pretty much useless

The A/C indicator light blinking is an indication that the system is low on refrigerant or a defective pressure sensor or wiring issue. The way you described your problem is that it is an intermittent one. The fact that your...

Coolant compatibility in f350.

Hello. I am not sure why they put Dexcool into your cooling system. Your truck requires the specific Ford coolant due to the design of the engine. There really is no reason why Dexcool should have been used, and if...

Related articles

How Long Does an AC Accumulator Last?
Your Your vehicle’s air conditioning system is a complex system of components, each of which plays an important role. However, not all the components will continue to work properly if they come into contact with moisture, and that is where...
How Long Should It Take a Heater to Warm Up in Cold Weather
When When you turn on your car’s heater, it should start blowing warm air. If the engine is already at operating temperature, this should happen immediately. However, if your engine is cold, it will take longer and if the weather...
A Buyer’s Guide to the 2011 Ford Ranger
The The 2011 Ford Ranger offers affordable pricing with excellent styling. It is a compact pickup that is both inexpensive to operate and own. The vehicle is capable of going off-road while still being able to tow 1,600 to 3,100...