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Engine 1990 302 high idle -only when Eng. is hot

  • Thread starter Thread starter Real time recon
  • Start date Start date Nov 4, 2018

Real time recon

Mustang Master
Aug 21, 2016
469
205
83
...
Nov 4, 2018
#1
  • Nov 4, 2018
  • #1
Morning all.
Just developed a problem .Eng. has high idle ,1,500 rpm....(ONLY) after its been running.Any ideas ?
Cold starts are perfect
1990 mustang GT 302/345hp.EFI
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
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polk county florida
Nov 4, 2018
#2
  • Nov 4, 2018
  • #2
Any codes? Check for vacuum leaks, sometimes heat expansion causes them. My throttle gets sticky after driving for a while, I think the peddle is just worn out, that's surprising cause it's usually matted to the floor!
 
Reactions: Real time recon

Real time recon

Mustang Master
Aug 21, 2016
469
205
83
...
Nov 4, 2018
#3
  • Nov 4, 2018
  • #3
General karthief said:
Any codes? Check for vacuum leaks, sometimes heat expansion causes them. My throttle gets sticky after driving for a while, I think the peddle is just worn out, that's surprising cause it's usually matted to the floor!
Click to expand...
yeah,that's what I'm thinking, a vacuum leak on one of the lines expanding due to heat.
 

Real time recon

Mustang Master
Aug 21, 2016
469
205
83
...
Nov 4, 2018
#4
  • Nov 4, 2018
  • #4
anyone know a "easy " way to do a smoke test w/o spending big bucks on a smok machine ?
 

Real time recon

Mustang Master
Aug 21, 2016
469
205
83
...
Nov 4, 2018
#5
  • Nov 4, 2018
  • #5
Smoke machine coming up
>>> View: https://www.youtube.com/watch?v=EhNQiIRsCCk
 

Real time recon

Mustang Master
Aug 21, 2016
469
205
83
...
Nov 9, 2018
#6
  • Nov 9, 2018
  • #6
Replaced IAC with new one,problem solved.Constant smooth idle with Eng. cold or hot .
 
Reactions: phoneman91, General karthief and a91what
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