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Car seems to buck with defrost on

  • Thread starter Thread starter Cantslowdown
  • Start date Start date Oct 15, 2006

Cantslowdown

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Jun 20, 2004
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Oct 15, 2006
#1
  • Oct 15, 2006
  • #1
My car seems to kinda buck almost like its missing but only dose it when the defrost is on it dose it sometimes at idle and even just driving down the road..I was thinking maybe iac..
 

the98stang

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Aug 12, 2005
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Oct 16, 2006
#2
  • Oct 16, 2006
  • #2
Cantslowdown said:
My car seems to kinda buck almost like its missing but only dose it when the defrost is on it dose it sometimes at idle and even just driving down the road..I was thinking maybe iac..
Click to expand...

Clean the IAC and the MAF. It that doesn't help, replace the IAC. Also replace the PCV and grommet. The TPS could also be the culprit...
 

Superhereaux

chicks make me feel inadequate
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Oct 16, 2006
#3
  • Oct 16, 2006
  • #3
does it do the same thing with the a/c running?
 
4

46gtsblown

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Oct 16, 2006
#4
  • Oct 16, 2006
  • #4
Sounds like the AC compressor cycling to me.
With the eng on and set up the same open your hood and watch the AC clutch, it the stumble happens when the clutch engages you have found the cause. This is normal operation.

Dwayne
 

Cantslowdown

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#5
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In the summer it was never noticed..The cycling was never felt..
 
K

Kilgore Trout

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Mar 30, 2005
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#6
  • Oct 16, 2006
  • #6
Could be low freon...
 

stangGT97

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Oct 16, 2006
#7
  • Oct 16, 2006
  • #7
Cantslowdown said:
My car seems to kinda buck almost like its missing but only dose it when the defrost is on it dose it sometimes at idle and even just driving down the road..I was thinking maybe iac..
Click to expand...

by defrost do you mean the rear window defrost, as in the button to the left of the steering wheel? cuz that would have nothing to do with the compressor... but I also have no idea why using it would cause stumbling
 

Cantslowdown

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#8
  • Oct 16, 2006
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I'll have to check the freon its posible that it is low..
 

Dope 97GT

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Oct 16, 2006
#9
  • Oct 16, 2006
  • #9
when i turn my windshield defrost on high the rpms drop some if thats what you mean. And if the cars cold it almost stalls out.
 

Cantslowdown

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#10
  • Oct 16, 2006
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I know that the ac and defrost put a pull on the motor but..When i had my ac on when it was hot i never really felt the pull at all..I hope mike might chime in see what the master has to say..
 
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