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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

what would cause???

  • Thread starter Thread starter MI95Cobra
  • Start date Start date Sep 27, 2007

MI95Cobra

New Member
Aug 20, 2006
451
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0
Oklahoma City
Sep 27, 2007
#1
  • Sep 27, 2007
  • #1
what would cause my car to die when i turn my defroster on????
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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129
Sep 27, 2007
#2
  • Sep 27, 2007
  • #2
Does the car stall with the AC on also? If so, the IAC might not be working properly.
 

94-302-vert

Active Member
Aug 16, 2004
1,947
2
36
NE CT
Sep 27, 2007
#3
  • Sep 27, 2007
  • #3
The defroster is causing it to die... don't use it...

In all seriousness... I would try disconnecting the defroster from the window then see if it still happens... could be a shorted out defroster causing a high electrical load...

Is the fuse blowing?
 

Yellow302

Member
Mar 2, 2003
789
2
19
NJ
Sep 27, 2007
#4
  • Sep 27, 2007
  • #4
turning on your AC/defrost adds a value to increase IAC to allow more air through due to the demand of the increased load on the engine. Try cleaning the IAC or you may want in give your TB screw a baby turn forward to increase your base idle a tad.

Or if you had a chip id just add more value to the IAC when the ac comes on.
 

MI95Cobra

New Member
Aug 20, 2006
451
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Oklahoma City
Sep 27, 2007
#5
  • Sep 27, 2007
  • #5
ok....so check the IAC...is there a way to check it???
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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129
Sep 27, 2007
#6
  • Sep 27, 2007
  • #6
MI95Cobra said:
ok....so check the IAC...is there a way to check it???
Click to expand...

You really need an oscilloscope to check it's function.

If you can view PIDs, you can get an idea of what is going on.

Otherwise, you might want to clean it. Here's a little article about doing it.

Good luck.
 

MI95Cobra

New Member
Aug 20, 2006
451
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0
Oklahoma City
Sep 28, 2007
#7
  • Sep 28, 2007
  • #7
thanks hissin5.o....there was alot of carbon built up on the smaller one....i'll try it out when i go to work tonight....
 

MI95Cobra

New Member
Aug 20, 2006
451
1
0
Oklahoma City
Sep 30, 2007
#8
  • Sep 30, 2007
  • #8
ok...i was told to clean my mass air sensor also....so i cleaned it and noticed it was idling better and no surging.....when i was at a red light i turned on my ac and noticed my battery gauge dropped from half to about 1/4....is that normal??? or any ideas???
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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Oct 1, 2007
#9
  • Oct 1, 2007
  • #9
That's not normal. When you turn on the AC, do the RPMs kick up?

If your idle drops too low, your alternator cannot keep up (you not only lower the alternator's speed [ergo output] but with the cooling fan, compressor and HVAC fan, you introduce a lot of electrical load).

Before the WCCT, I had to artificially raise my mechanical idle setting to help with a similar issue.

Good luck.
 

MI95Cobra

New Member
Aug 20, 2006
451
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0
Oklahoma City
Oct 1, 2007
#10
  • Oct 1, 2007
  • #10
ok...should i increase my timing or open my throttle more???
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Oct 1, 2007
#11
  • Oct 1, 2007
  • #11
Personally I'd turn the idle up.
 

MI95Cobra

New Member
Aug 20, 2006
451
1
0
Oklahoma City
Oct 1, 2007
#12
  • Oct 1, 2007
  • #12
so you think it my be my new alternator????
 

toyman

10 Year Member
Jul 19, 2007
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79
Vernon BC
Oct 1, 2007
#13
  • Oct 1, 2007
  • #13
Quite possibility. Output voltage should be 14+v. If there is a local auto/marine electrical repair facility in your area they might best be able to help. They will have the ability to test and repair/rebuild the alternator as required. In my experience it's a better alternative than just replacing the unit
 
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