fan blows to defrost when climbing hills
#1
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Model: Grand Cherokee
Engine: 4.0
fan blows to defrost when climbing hills
in my 2000 cherokee laredo, 4.0 2wd , when climbing a hill or accelerating heavy the ac blows thru the defroster, then moves back when condition goes back to normal driving . also, without the ac or anything on the inside of the windshield fogs up doing the same thing , up hill or acceleration. What do i look for and appprox. where ?
#3
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Year: 1999
Model: Cherokee
Engine: 4.0 L
Test the check valve thats inline with the vacuum hose going from the intake manifold to the fire wall. That was my problem. The vacuum was escaping when the engine vacuum dropped.
#4
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Model: Cherokee
near the battery there is a hard 1/4" vacuum line that runs to the vacuum reservoir under the bumper. Ive had 2 that rubbed on the battery putting a hole in that line.
Also ck the reservoir cannister under the bumper and make sure it hasnt been knocked loose from it.
Also ck the reservoir cannister under the bumper and make sure it hasnt been knocked loose from it.
#6
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Year: 1998
Model: Cherokee
Engine: I6
#7
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Year: 1998
Model: Cherokee
Engine: 4.0 I6
My '98 also does this whenever I am on the Freeway, but not at surface street speeds. It actually switches back and forth between the Defrost and the Vent continuously while on the freeway.
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#8
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Year: 1994
Model: Cherokee
Engine: 4.0 H.O. K&N, Borla headers, custom down pipe, magnaflow hi-flo cat, flowmaster to turn down tip
in my 2000 cherokee laredo, 4.0 2wd , when climbing a hill or accelerating heavy the ac blows thru the defroster, then moves back when condition goes back to normal driving . also, without the ac or anything on the inside of the windshield fogs up doing the same thing , up hill or acceleration. What do i look for and appprox. where ?
#9
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Year: 1987
Model: Cherokee
Engine: 4.0
Easiest way to track a leak....get a can of carb cleaner and spray around vaccum lines when the rpm's raise ur in/on/around/near the leak good luck!!
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