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

34

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

8,054

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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.