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  • SN95 4.6L Mustang Tech

Idle Problem?

  • Thread starter Thread starter sonicstang00
  • Start date Start date Jun 28, 2011
S

sonicstang00

New Member
Jun 27, 2011
4
0
0
Jun 28, 2011
#1
  • Jun 28, 2011
  • #1
Alright guys hopefully someone can help me, Everytime i apply the clutch before i shift the car idles up to about 2-2500 rpms and sticks there, I replaced the iac already and checked my hoses and none have holes in them thought maybe a vaccum leak, any suggestions?
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
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204
Houston Texas
Jun 28, 2011
#2
  • Jun 28, 2011
  • #2
Check all fuses. If this is a 99-04 MY, check fuse F2.2 and F2.8.

Any mods? After market TB? Have you attempted to adjust the idle set screw? Is the throttle return spring closing the TB fully? Do the throttle linkage move smoothly and freely?

A bad TPS can cause a hanging high idle. The best way to trouble shoot is to monitor the TP-MODE PID. This will indicate if the PCM is seeing a good closed throttle TPS signal.

A vacuum leak after the TB butterflys can also cause a high idle. What about the PCV system? Remember that it's basically a controlled vacuum leak.

Please review:
Ford Mustang Forums - View Single Post - Is your mustang stumbling, dieing at idle or idling rough?
 
S

sonicstang00

New Member
Jun 27, 2011
4
0
0
Jun 28, 2011
#3
  • Jun 28, 2011
  • #3
Thanks! im gonna bring it in the shop and test these! I hooked it up to the scan tool tonight but nothing was out of its range so It leads me to think that the iac is sticking...second one i have put on this car.
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
Jun 29, 2011
#4
  • Jun 29, 2011
  • #4
So you confirmed the TP-MODE PID?

IAC's don't normally have such a short service life. Since the IAC has been replaced twice, IMO this leads weight to it being another problem. Which if there aren't any vacuum leaks, a bad TPS is high on the list.

Good luck.
 
S

sonicstang00

New Member
Jun 27, 2011
4
0
0
Jun 30, 2011
#5
  • Jun 30, 2011
  • #5
Fixed it, the TB was sticking i suppose i switched it and put the stock one back on and it hasnt done it since!
 
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