QuestionDear Sir,
My car is Nissan Maxima 2002, without ABS, Mileage is 100K mile, never faced any issues with brakes, but during the periodic inspection the car failed twice due to the rear brakes are not strong enough,
After the first failure, I've turned the rotors, changed the pads, flushed the brake oil, and bled the system, but again failed in the second inspection for the same reason.
No fixes for the brake booster or the master cylinder or the calipers were performed since manufactured since no issues.
All the mechanics who inspected the car, suggested to cancel (bypass) the proportioning valve to improve the rear brakes and get the car passes the periodic inspection, but I know the side effect of this and how the rear wheels may lock first and causes a lose of control then.
Unfortunately, this proportioning valve is not available in my region nor the rebuild kit, so my questions are:
1- This weakness of the rear brakes, could it be due to the proportioning valve?
2- Faulty proportioning valve causes the rear hydraulic pressure to go above what it was designed for not less I think, right? #i.e. if the front rear pressure of 1000 psi the rear should be 700 psi, so for a faulty proportioning valve it should allow more pressure to pass to the rear so it reaches more than 700, not to be less than 700#
3- In case the proportioning valve is just semi clogged, how can I clean it, (i.e. put it in some diesel, brake cleaner, petrol, or just wash it with water and soap)
Thanks in advance...
AnswerHi Ehab -
Yes, sure sounds like the proportioning valve. Have you tried the dealer? They are the ones that carry it. Also if you check on line, I am sure you can find one.
The valve is not usually serviceable, although sometimes you can remove it and clean it by getting brakleen and spray each orifice while pushing the reset button back and forth. Do not use water or any other substance other than brakleen of brake fluid.
Hope this helps -
aloha
calvin
