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

RPM's Dropping...?

  • Thread starter Thread starter impulse001
  • Start date Start date Apr 7, 2008
I

impulse001

New Member
Jan 16, 2008
84
0
0
New Jersey
Apr 7, 2008
#1
  • Apr 7, 2008
  • #1
So when I idle my car, the RPM's drop to around 650, and as its sounding like it's going to shut off, they shoot back up to 1000/1100.. Drives fine, and if I give it some gas it will stop doing it for a little, but then start again.

I took out the throttle body a few days ago to clean it, could It have something to do with that?
 

bloopbloob

Member
Sep 27, 2006
578
4
16
Alberta
Apr 7, 2008
#2
  • Apr 7, 2008
  • #2
codes. did you change anything with the tps or iac? could be a lot of things. dump the codes.
 

5.0Droptop

...all those nights we shared, and you're a dude??
Special Agent Mukity-Muck Whats in Charge Round Here
May 15, 2002
1,785
1,130
233
Indiana
Apr 7, 2008
#3
  • Apr 7, 2008
  • #3
Did you replace the alt yet? If not its running on low voltage it will make it act strange.

Taking the TB off could have messed with the idle settings and TPS settings.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,299
18,005
224
Massachusetts
Apr 7, 2008
#4
  • Apr 7, 2008
  • #4
Reset the idle.

Unplug the IAC and let the engine idle. Adjust the idle using the idle stop screw to bare minimum idle (the lowest it will go while letting the engine idle)

reset the computer

plug IAC back in

start car and let it relearn idle strategy
 

5.0Droptop

...all those nights we shared, and you're a dude??
Special Agent Mukity-Muck Whats in Charge Round Here
May 15, 2002
1,785
1,130
233
Indiana
Apr 7, 2008
#5
  • Apr 7, 2008
  • #5
word...

Check tps while at it....Test with digital volt meter, Use the black wire as ground green wire is positive. Set it to .97-.99 volt. To adjust it loosen the 2 screws and turn + or -
 

mustangfan1990

New Member
Jul 17, 2005
505
1
0
Lenoir, North Carolina
Apr 7, 2008
#6
  • Apr 7, 2008
  • #6
my car does the same thing and I have tried every trick in the book. I finally got mine fixed when I got mine tuned
 

fiveohwblow

Official Member
15 Year Member
Jul 21, 2005
2,169
145
155
Apr 8, 2008
#7
  • Apr 8, 2008
  • #7
mustangfan1990 said:
my car does the same thing and I have tried every trick in the book. I finally got mine fixed when I got mine tuned
Click to expand...

+1. The other ways mentioned will fix manual problems but I have had the same issue both before one tune, and after another. Point is it can be tuned out if your tuner knows what he is doing.
 
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