2000 subaru outback stalls when braking

subaru
stall
electrical-wiring
lights
stalls
outback

#1

hi all, mine is an outback, which yesterday when having to brake suddenly in a store parking lot, it caused the car to stall. i have noticed in times past that during night time driving, when applying the brakes, the lights will momentarily dim. any ideas ?


#2

If the battery is more than four years old, buy a new one. Otherwise, maybe a weak alternator, and otherwise, how’s your car’s idle in drive? Is it at about at least 1,000 rpm’s and is it consistent? If not, you have some other problem.


#3

thanks for your response. the battery is only 2 yrs old. while idling in drive, its a little less than 1000rpm at first, then it will slowly drop to around 750 & stay there. it also does not shake or sputter while idling, but is rather smooth.


#4

Once you stop, what happens if you apply the parking brake, take you foot off the brake and then put your foot back on. What I am trying to do is to determine if it is the slowing down or the foot on the brake that is causing the problem.


#5

"Is it at about at least 1,000 rpm’s?"
Hopefully not!

The correct idle speed for a warmed-up Subaru 4-cylinder engine is between 600-700 RPMs.
If the engine is idling at 1,000 RPMs after it is warmed-up, then that is an indication of problems–possibly with the IAC.

For the OP’s situation, I would explore possibilities of a problem with the power brake booster.
This could be a vacuum problem that is stalling the engine when the brake is applied.


#6

thanks. the idle speed after the warm up is around 660 in park, & a little less than that in drive. when applying the (foot) brake when the emergency brake is on, whether in park-neutral-or drive, the rpm needle will shoot up about 100 more rpm, then go back down.