Q: poor brake performance when car's ac is on
When driving with ac system on. Usually in warm / hot weather. Braking performance is significantly poor. Pushing harder on the brake pedal doesn't seem to help. Wondering if this is common? How would I fix the issue?
My car has 230000 miles.
My car has an automatic transmission.
Hi there. Most of the time this is due to a loss of vacuum in the engine. A loss of vacuum drastically reduces the performance of the power brakes. I typically start by checking for any vacuum leaks in the engine. If there are none, then it may need a new vacuum booster. If you are going to have this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to inspect your braking issue and make any repairs that are necessary.
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
What others are asking
When turning left, car dies
Hello. This is a very rare and strange problem to have in a car. My thought is that something is putting too much load on the car when you are turning left. A load is when a component of the...
My horn started going off for no reason then when I was driving yesterday my car stop going and I had to pull over.
When a horn (https://www.yourmechanic.com/services/horn-replacement) goes off like this, it is usually because something in the steering column has come loose making an electrical connection for the horn. This will require the disassembly of the horn pad to investigate. Often this...
Heater blows cold air when vehicle is stopped.
You may have a clogged heater core that may be prohibiting the outer linings of the heater core to get hot. As you know, the heater core is a series of tubes that the coolant runs through that generates the...
Car accelerates very slow when it hits 20 mph and neutral shift on dash starts to blink.
Either the transmission has thrust bearings or bushings that are worn causing the internal parts to go out of balance or there is an issue with the fluid is low causing the gears to slip. If the fluid is full...
Clicking Sound
What you are describing sounds like a faulty starter solenoid (https://www.yourmechanic.com/services/starter-replacement). A faulty starter solenoid will generally produce a clicking sound when turning the key. The starter solenoid is located on the starter and has internal electrical contacts that transmit...
Car shaking
Vibration at idle is due to either failed motor/transmission mounts or an engine operating condition that causes a rough idle. If you are getting vibration through the steering wheel at speed, the most common cause is a wheel/tire imbalance although...
My power outlets stay on after turning off car. I want them to stop supplying power after I turn off car. 2010 Ford Focus.
Your power points are supplied direct battery through fuses 3 and 15 in the battery junction box. You would need to alter the wiring of them to have them switched power.
Code on Subaru Forrester 2005 is PO335
Code P0335 relates to the camshaft position sensor not transmitting a proper signal to the PCM. The camshaft position sensor (https://www.yourmechanic.com/services/camshaft-position-sensor-replacement) measures the rotational position of the camshaft and transmits that information to the engine control computer. To determine which...
Method used to replace clutch fluid
There are two different methods that can be used. One is to use pressure on the master cylinder with fluid and push new fluid through the system. The other method is to use a vacuum at the clutch slave cylinder...
Related articles
How Long Does an AC Fan Control Module Last?
The The AC fan control module is what controls both the cooling fans in the front of your car’s radiator, and the blower motor in the passenger compartment. It is mounted within the engine compartment, and that means that it...
How Long Does an Electronic Brake Control Module (EBCM) Last?
Technology Technology has come a long way where cars are concerned, and the braking system is one area that has really benefitted from advances. There are now all kinds of safety features that are built into the braking system that...
How to Replace a Heater Blower Motor Switch or Relay
The motor switch on your heater and air conditioning goes bad when the switch gets stuck in certain positions or will not budge at all.
Browse other content
Services
Maintenance