My Montero sport 2002 3.5



Here is a picture looking down on the master cylinder and the accumulator on the firewall. What is the electrical wire that runs to an electrical connection that runs to the master cylinder. I’ve been having a buzzing sound when I’m going 5mph and applying brakes.


barry

 

Electrical wire is probably brake fluid level indicator and on leter Monteros ut is power suply to the electric booster pump. Does the buzzing noise occur when you depress the pedal? If so, it could be a faulty or failing vacuum booster

 

Yes and iit only happens when the car has sat overnight. It will happen in the first 6 or so times you brake then it won’t do it again that day. If I have two trips in a day it will happen in the first one but not the second.

it’s a buzzing and hissing sound

 

So, it looks like 2002 Montero Sport does not use electrical pump and hydraulic brake booster, that is only on full size Montero. Yours has a vacuum brake booster (big dish bolted to the firewall). In this case, the electrical wires on the master cylinder are likely to be fluid level sensor and ABS system. The buzz you hear is probably ABS system trying to control proportioning of braking to different wheels. Do you have "Brake" or "ABS" lights illuminated on the dashboard? Is your braking / stopping distance worse than before? If so, your may need to replace your master cylinder, since there are probably no serviceable parts inside of it.

 

I pulled the relay a few weeks ago due to a wheel sensor issue. We don’t really need ABS down here in the south. Would the AbS engage with the relay pulled ?

it only happens the first few miles driven once it is “warmed up” it don’t do it. The break doesn’t feel any different other than I can feel a slight vibration when that happens. I ran some test I saw on the online and the actuator accumulator seems to be working. The pedal doesn’t get hard or soft.

barry

 

Its possible that the buzz you describe is related to ghd relay. Can't be sure one way of the other- not too familiar with Sport versions