brake booster vacuum leak?

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duster97
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Posts: 51
Joined: Tue May 05, 2015 10:45 pm
My tercel:: 1985 tercel 2wd

brake booster vacuum leak?

Post by duster97 »

Is it normal to have your engine rev down when you pump the brakes, or is that an indicator of a vacuum leak?
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marlinh
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My tercel:: 'Everett' Blue 87 4WD Wagon (Rocky 86, recently retired)
Location: Kootenays

Re: brake booster vacuum leak?

Post by marlinh »

That doesn't sound normal. There shouldn't be any change in engine speed when you brake. Maybe a vacuum leak or a bad booster? What do the brakes feel like?
duster97
Advanced Member
Posts: 51
Joined: Tue May 05, 2015 10:45 pm
My tercel:: 1985 tercel 2wd

Re: brake booster vacuum leak?

Post by duster97 »

It's only when I pump the breaks like several times. They car still stops just fine. It doesn't really feel like anything is wrong with the breaks I think.
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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: brake booster vacuum leak?

Post by Petros »

several pumps of the pedal depletes the reserve vacuum in the booster, so it would likely make a small change in idle speed once you empty the vac booster of vacuum. verify you do not have any other vacuum leaks of course, but it does not sound like anything unusual.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
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