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idel problems on a 1990 GT

  • Thread starter Thread starter fastback65chris
  • Start date Start date May 26, 2004

fastback65chris

New Member
Mar 26, 2002
46
0
0
Wichita Kansas
May 26, 2004
#1
  • May 26, 2004
  • #1
I have a 1990 GT and when the engine is hot and I have the a/c on the idel will run from 800 to 2000 rpm until the car amost dies can anyone help me on this. Also when the engine is hot the starter will drag when starting. I have already replaced the starter with a new one and still have the same issue I have also replaced the voltage regulator and the coil
 

SCORPION

New Member
Mar 2, 2004
386
0
0
Seaford, DE
May 26, 2004
#2
  • May 26, 2004
  • #2
I just fixed this problem on my 90 LX....

You have to make sure your TPS is getting the right amount of juice. I don't know the exact proceedure, but contact M8KMDAY (he did mine) and he will be able to walk you through the process.
 

fastback65chris

New Member
Mar 26, 2002
46
0
0
Wichita Kansas
May 26, 2004
#3
  • May 26, 2004
  • #3
was it a minor adjustment or did you have to replace something and does your stang run real hot at idel
 

fastback65chris

New Member
Mar 26, 2002
46
0
0
Wichita Kansas
Jun 8, 2004
#4
  • Jun 8, 2004
  • #4
I replaced my tps and this seemed to fix the idel issue with the cold start up but I also have another issue when you turn on the ac and the it kicks in it drops my idel down by 400 rpms and when the cluthc on the compressor disengages the idel comes back up to 800 do you know what part controls your idel when your compressor kicks on or what part idels your car up when your compressor turns on?
 

bmorrisj

Member
Sep 26, 2003
449
0
17
Buena Park, CA
Jun 8, 2004
#5
  • Jun 8, 2004
  • #5
its your iac....the eec is supposed to compensate with the engine load from the A/C.... disconnect the battery and let the eec relearn idle...
 
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