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1991 mustang GT HELP

  • Thread starter Thread starter Jim925
  • Start date Start date Aug 27, 2018
J

Jim925

Member
Aug 27, 2018
62
2
8
Ithaca ny
Aug 27, 2018
#1
  • Aug 27, 2018
  • #1
I recently bought a 1991 fox body 4 months ago and was told the motor needed a rebuild or a stroker kit installed, the motor smoked real bad, I bought a nice looking fresh 302 5.0 off craigslist, the motor has a 97 explorer intake and plenum. I took out the old and put in the new, bought a gasket for the plenum, tightened everything down and plugged in, first time starting it up the headers turned so hot in 30 seconds they looked like they were turning to slag, I was told timing and vacuum, the timing was way off and their was some vacuum leak, corrected this issue and started it back up, sounded good but still really hot and a idle at 2500 rpm, narrowed it down to IAC, I didn't have cash at the time i placed the IAC in a can of gas for couple hours and shook the piss out of it to clean all the gunk off the valves that are inside IAC, after this it idled at just under 1000 rpm, and now it takes about 5 min for the headers to start glowing, this car had nos hook ups and an extra ECU in the car, it is currently hooked up to an A9S the original is A9L which is unhooked, I am not a mechanic by far and can't afford one, which is why I'm here, I need some 1 on 1 help please!
 
J

Jim925

Member
Aug 27, 2018
62
2
8
Ithaca ny
Aug 27, 2018
#2
  • Aug 27, 2018
  • #2
The old motor the new motor
 

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J

Jim925

Member
Aug 27, 2018
62
2
8
Ithaca ny
Aug 27, 2018
#3
  • Aug 27, 2018
  • #3
Also am using the old TB, removed the bar in the back of the motor, also the explorer intake does not have a spot to hook up the TB coolant line
 

jrichker

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#4
  • Aug 27, 2018
  • #4
Have you checked the ignition timing with a timing light?
What sort of vacuum are you getting at idle?
What happens to the idle if you unplug the electrical connector on the IAC? Does the RPM decrease or remain the same?
 
J

Jim925

Member
Aug 27, 2018
62
2
8
Ithaca ny
Aug 27, 2018
#5
  • Aug 27, 2018
  • #5
Yes the timing was set with a light and I just checked it again, I unplugged the IAC and the idle dropped down
 

jrichker

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Dublin GA
Aug 28, 2018
#6
  • Aug 28, 2018
  • #6
Jim925 said:
Yes the timing was set with a light and I just checked it again, I unplugged the IAC and the idle dropped down
Click to expand...
What sort of vacuum readings are you getting?
 
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