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Idle Problem Continued

  • Thread starter Thread starter smoore2199
  • Start date Start date Apr 7, 2004
S

smoore2199

Founding Member
Nov 19, 2001
93
0
0
NJ
Apr 7, 2004
#1
  • Apr 7, 2004
  • #1
Still having weird idle problems...I just replaced the Throttle Position Sensor, Idle Air Control Valve, and the Phelum. The car idles too high at rest the movie shows this...once i unplug the IAC plug the car idles normal, but if i drive it with the IAC unpluged the car still has a tendoncy to hang around 3k rpms. The check engine light was on and i get P1504 which is Idle Air Control Circuit (duh I unplugged it). I've replaced almost everything, is it possible that I replaced a bad IAC with a bad IAC?

MOVIE HERE
http://www.spencerdmoore.com/idle.mpg
 
B

Bulldog6Z6

New Member
Jun 20, 2003
163
0
0
Houston Texas
Apr 7, 2004
#2
  • Apr 7, 2004
  • #2
my did the exact same thing, i have just been running it wit out the iac (it revs down quicker too).
 
S

smoore2199

Founding Member
Nov 19, 2001
93
0
0
NJ
Apr 7, 2004
#3
  • Apr 7, 2004
  • #3
Yeah but the rpm still hangs around 3000 when driving, and the car feels like its running like crap.
 

Dan_Soprano

15 Year Member
May 7, 2003
7,410
54
129
Jacksonville, FL
Apr 7, 2004
#4
  • Apr 7, 2004
  • #4
Did the idle kick down when you unplugged the Throttle Position sensor? If not then next likely cause would be a vacuum leak somewhere.
 
S

smoore2199

Founding Member
Nov 19, 2001
93
0
0
NJ
Apr 7, 2004
#5
  • Apr 7, 2004
  • #5
Unplugging the TPS has no effect. I sprayed some TB cleaner around the intake and didnt get any surge so i assume that there is no vacuum leak. The only time the rpm drops back down to normal is when i unplug the IAC connector.
 

Dan_Soprano

15 Year Member
May 7, 2003
7,410
54
129
Jacksonville, FL
Apr 7, 2004
#6
  • Apr 7, 2004
  • #6
Try a new IAC valve I suppose then.....did you save the recipt from the old one? I got a bad EGR valve a few weeks ago from pepboys. It is possible.
 
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