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Tim Mohr
Tim Mohr, ASE MASTER TECH
Category: Car
Satisfied Customers: 15434
Experience:  30 YRS EXPERIANCE, AUTO AND TRUCK,FOREIGN AND DOMESTIC, GAS AND DIESEL
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mazda 3: stop sign..car starts..I put on emergency brake..brake switch

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My mazda 3 2004 when at a stop sign in gear and foot on brake car starts to idle down below 500 rpm and beyond.. When I put on emergency brake and take foot off brake it returns to normal idle. Is there something on brake switch that could cause this. My other mazda did the same thing.

TIM MOHR :

Hi, my name is XXXXX XXXXX is caused by a bad diaphram in the vacuum brake booster, and when you press the brakes, it leaks and causes a vacuum leak, which in turn lowers the idle, replace the vacuum booster for the brakes and you will be good to go,Tim

JACUSTOMER-quow0hib- :

If this fixes the problem good, but if not does it cause another trip and another 23.00 to say it did not work.

TIM MOHR :

if the car idlles fine with the e brake on, and not pressing the brakes, then its in the booster, nothing else will cause this, it is very common, if you have more questions about this at a later date, just return to this question, and i will help you, you wont be charged again,Tim

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