Chrysler Repair: hi agian my recent question..., pollution mitigation, heavy duty springs

Question

  hi agian  my recent question about the brakes making nosic , i check the anti rattle chips and the were fine i also clean the caplier  slide  and it sill make the no nosic like old beb spring the brake pads have a good amount of milage on the so what esle do you think the nosic is and were it is i can hear it but can't fine,
  the other question is my car don't have a air pump or a electronic pump so how do the emisson eork on this car thank you for the help tim

Answer
Hi Tim,
You haven't mentioned what brand and model of car you are dealing with so let me know what that it is, please. For example, there are definitely brake shoe return springs used in drum type brakes, so if the rear axle of the car uses drum brakes those heavy duty springs could be the source of the noise. I would have a helper operate the brake pedal while you listen carefully at each of the four wheels to hear if you can locate which brake unit(s) is/are making the noise.
The air pump used for pollution reduction went out with the onset of the fuel injection/engine computer systems which were more sophisticated and could very the timing/mixture to achieve pollution reduction without a pump.
Again, whether that is the case with your car depends upon its year. So let me know that and maybe we can determine what it is supposed to have on it for pollution mitigation.
Roland