Question about 1988 Ford F 250

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Brake vacume problem

How many inches of vacume should my vacume pump produce, and how many inches of vacume are required to operate the brake booster? This is on a 1988 ford f250 diesel.

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16 to 20 at idle and 20 to 22 at the most diesels also use a auxillary pump to get the vaccum because it has no trottle there for no vaccum, might want to check that also.

Posted on Apr 20, 2009

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sense its a deisel i would go with the vacume pump, diesels don't put out any or very little vacume, if you don't have vacume than booster won't work hense hard peddel. when you say you let up on peddel and hit it again you got better break tells me it is not getting enought vacume to booster. i would go for the vacume pump.

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