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1987 Mustang Idle Speed

  • Thread starter Thread starter Lynx331
  • Start date Start date Aug 24, 2004
L

Lynx331

New Member
Jan 5, 2004
308
0
0
Chicago IL
Aug 24, 2004
#1
  • Aug 24, 2004
  • #1
What is the stock 87 mustang gt idle speed. My throttle body was sticking, so we adjusted the idle speed screw and now its at 1000*, but no stick pedal? Anyone kno what the stock rpm should be?
 

stockhatch

Founding Member
Oct 9, 2001
536
0
16
polar sloth country
Aug 24, 2004
#2
  • Aug 24, 2004
  • #2
Around 900 I think is the stock idle point. Its definitely below 1000. The throttle plate doesnt really control idle speed anyways. It should be closed and the IAB solenoid should control the idle. You may want to check your TPS now that you have changed the butterfly though.

AC
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Aug 25, 2004
#3
  • Aug 25, 2004
  • #3
The computer tries to control it somewhere in the 875-700 rpm range. But the tachs are notoriously inaccurate -- so be sure you're using a calibrated tach.
 

Mavrick

Founding Member
Aug 29, 2002
2,264
0
46
Collingwood, ON
Aug 25, 2004
#4
  • Aug 25, 2004
  • #4
I always thought it was 650.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Aug 25, 2004
#5
  • Aug 25, 2004
  • #5
The number I've seen printed somewhere (maybe Probst) is 672....like our tachs will actually read that close!
 

bit

Founding Member
Sep 27, 1999
1,975
1
48
Anderson, SC
Aug 25, 2004
#6
  • Aug 25, 2004
  • #6
Mavrick said:
I always thought it was 650.
Click to expand...
Yeah listen to Mavrick, the stock idle is 650RPMS.
 
9

90pony302

New Member
Mar 16, 2004
65
0
0
southern illinois
Aug 25, 2004
#7
  • Aug 25, 2004
  • #7
I think my chilton manual says 900. But to me that was way to high. idled it down and changed the tps position and you can definitely hear the cam now.
 

Mavrick

Founding Member
Aug 29, 2002
2,264
0
46
Collingwood, ON
Aug 25, 2004
#8
  • Aug 25, 2004
  • #8
Michael Yount said:
The number I've seen printed somewhere (maybe Probst) is 672....like our tachs will actually read that close!
Click to expand...

Ya, 675 sounds about right too. I'm sure it was either 650 or 675.
 
4

4montecarlo

New Member
Feb 26, 2004
16
0
0
Aug 25, 2004
#9
  • Aug 25, 2004
  • #9
i think the manual calls for 2 different idle rpms, depending on tranny, with auto is was like 650 and with t5 like 850,
matt
 

bmorrisj

Member
Sep 26, 2003
449
0
17
Buena Park, CA
Aug 25, 2004
#10
  • Aug 25, 2004
  • #10
4montecarlo said:
i think the manual calls for 2 different idle rpms, depending on tranny, with auto is was like 650 and with t5 like 850,
matt
Click to expand...

that does make more sense.....it would be tedious trying to just roll a t5 at 650 without bucking and stalling....
 
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