Stals when a/c control is moved to any vent position

F

FiveOfastback

New Member

Dec 25, 2004

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Bethlehem, pa

Aug 25, 2005

#1

• Aug 25, 2005

• #1

Stalls when a/c control is moved to any vent position

My 88 stalls whenever a vent position change such as floor or mix or a/c> Are the selector switches prone to problems? HELP!

 

HISSIN50

"How long does it take to get help in here?

15 Year Member

Nov 29, 1999

31,179

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129

Aug 25, 2005

#2

• Aug 25, 2005

• #2

There is an extra load created on the motor when the A/C is turned on. The IAC is responsible for bumping the idle up to accomodate this.

And the system can bog when switching the HVAC fan on to a higher speed. This can be normal - the alternator can take a second to accomodate the increased load.

Good luck.

 

F

fiveofanatic

How to fuel a Mustang:

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Aug 12, 1998

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Phoenix, AZ suburbs

Aug 25, 2005

#3

• Aug 25, 2005

• #3

Big ol' vacuum leak, maybe?

 

2000xp8

SN Certified Technician

Aug 8, 2003

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NJ

Aug 25, 2005

#4

• Aug 25, 2005

• #4

fiveofanatic said:

Big ol' vacuum leak, maybe?

Click to expand...

Exactly what i was thinking.

The vacumm is used to keep the valves in different positions. I think naturally it's on floor, that's why it doesn't do it all the time.

 

QDRHRSE

New Member

Dec 31, 2002

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Palmdale, CA

Aug 26, 2005

#5

• Aug 26, 2005

• #5

2000xp8 said:

Exactly what i was thinking.

The vacumm is used to keep the valves in different positions. I think naturally it's on floor, that's why it doesn't do it all the time.

Click to expand...

Me too. The heat & AC controls are vacuum operated.

 

HISSIN50

"How long does it take to get help in here?

15 Year Member

Nov 29, 1999

31,179

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Aug 26, 2005

#6

• Aug 26, 2005

• #6

A vac leak should cause a higher or hanging idle, not stalling.

Here is a marvelous drawing of the pathways for the HVAC.
Good luck.