Q: Squealing when driving and breaking and rpms jump by 500 while driving.

asked by on December 28, 2016

When i am driving a high pitched squeal happens intermittently when i brake sometimes. Also the rpms will jump up by about 500 almost viciously while driving even at a steady pace. What can i do to fix this?

My car has 240000 miles.
My car has an automatic transmission.

Brake Pads Replacement $150.17 - $479.65 Get a Quote
Mass Airflow Sensor Replacement $188.36 - $786.53 Get a Quote

Hello There, It sounds like you may have two separate issues going on here. The squealing sound is likely your brake pads which have wear indicators on them that are designed to produce a squeaking sound signaling that it may be time to replace them soon. The RPM fluctuation may be due to a dirty or faulty mass air flow sensor. The mass air flow sensor monitors air intake as it is mixed with fuel prior to being injected into the motor. This sensor relays vital information to the ECM which uses this to make adjustments to fuel supply to the motor. A dirty or faulty sensor can cause an imbalanced air/fuel load to be supplied to the motor which results in an over fueling or under fueling situation depending on the conditions causing a jerking reaction or loss of power in some cases. I would recommend having a professional from YourMechanic come to your location to diagnose and inspect your vehicle.

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