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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

1050 rpm idle

  • Thread starter Thread starter DJHA90
  • Start date Start date Oct 29, 2007

DJHA90

Member
Dec 17, 2002
581
0
16
Texas
Oct 29, 2007
#1
  • Oct 29, 2007
  • #1
I can't seem to get my idle down where it is supposed to be. I have cleaned the MAF, the throttle body, and the IAC. I have set the TPS to .95 volts. The throttle set screw is just barely touching the stop. The idles are set to 700 via the tweecer. What do I need to do / check next?
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Oct 29, 2007
#2
  • Oct 29, 2007
  • #2
I'd be willing to bet its something mechanical

Is this something that just started or what

What do you see in your dlog for a closed throttle voltage

Are you sure your isc is operating correctly

Do you possibly have your tb bleed screw too far out

Grady
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Oct 29, 2007
#3
  • Oct 29, 2007
  • #3
Vacuum leaks will kick the idle up.

Like Grady said, check the IAC screw. Factory is 1.5-2 turns left from bottomed out.

Also, highly advanced spark at idle will kick the RPMs up.

How low can you get it to idle with SPOUT out and IAC unplugged?

Wes
 

DJHA90

Member
Dec 17, 2002
581
0
16
Texas
Nov 4, 2007
#4
  • Nov 4, 2007
  • #4
So I wnet to work on my car again today. TPS is up to 1.020 (I had it measured at .95 volts last time I worked on it.).

I unplugged the spout, the tps, and IAC -- the RPM cam down to about 850.

Vacuum it at about 20.

Ideas?
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Nov 4, 2007
#5
  • Nov 4, 2007
  • #5
How's that ISC bypass screw look? It's under a white plug on the throttle body -- an allen wrench will turn it. Screw it all the way in (count the # of turns). As said above 1.5-2 is factory spec.

If you are within the spec, I would start thing vacuum leak or sticking ISC if you are still idling that high w/ the SPOUT and ISC unplugged.

Wes
 

DJHA90

Member
Dec 17, 2002
581
0
16
Texas
Nov 10, 2007
#6
  • Nov 10, 2007
  • #6
Took my FMS 65mm TB off and put the stock TB on. (put the IAC from the 65mm onto the stock TB) Now it is idleing down where it should be... So it looks like the IAC is good and the VAC should be good. Once it gets warmed up and I drive it for a while -- I get some surging idle and the car sometmes dies from low idle. That is probably due to the larger maf and 24lb injectors.

Im thinking about putting everything back to stock and sell the parts Its been fun messing with it over the last couple of years -- but im missing how smooth the car use to run. Then again...
 
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