Technician A says a pull to the right during braking could be caused by a defective metering valve. Technician B says a pull to the left could be caused by a defective proportioning valve. Which technician is correct

The correct option is;

Neither A nor B

Explanation:

The common cause of a vehicle pulling to the right or to the left during braking is due to a contaminated breaking surface or a faulty caliper. Other causes include tire size variation or worn out suspension components.

Other causes include;

Leaking break fluid

Piston frozen in wheel cylinder or caliper

Adjuster of rear break

Tire fault.

As soon as it is observed that the vehicle pulls on one side when braking, the vehicle should should be taking for checks by a qualified mechanic as soon as possible.