Mechanics

VACUUM ISSUES

1994 Toyota 4Runner

Brakes problem
1994 Toyota 4Runner 6 cyl Four Wheel Drive Automatic 112000 miles

Break pedal hard (no assist at all). Engine runs fine, there was an issue with vacuum leaks but I think I have it solved. There is now vacuum at the booster. How much vacuum should be present at idle? Can the booster go bad from prolonged loss of vacuum to it? What should the vacuum system pressure be?
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Richie923
March 2, 2009.




Hi there,

Check that the vacuum check valve at the booster is not faulty, max idle vacuum is 21" mercury but often 18-19 is ok, I would be checking that there is vacuum at the check valve first.

Mark (mhpautos)
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Mhpautos
Mar 2, 2009.
I didn't even think about that. Thank you very much. Or as we say in Hawaii " Mahalo"

Tiny
Richie923
Mar 2, 2009.

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