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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Car wont hold idle all of the sudden!

  • Thread starter Thread starter 98laseredgt
  • Start date Start date Aug 10, 2004
9

98laseredgt

New Member
Jul 16, 2004
122
0
0
indianapolis
Aug 10, 2004
#1
  • Aug 10, 2004
  • #1
i drove my car to work today at 6am. ran fine, started right up and idled smooth at about 800 rpm. i turn it off at work and go to leave at about 10:30 and the car wont idle and keeps dying. i been meaning to put the new plugs in. so i go home and let it "run" in my parking spot (apt. complex). and it idles at like 400 and drops to 200 and picks back up. like a cam only not. i checked all the vacuum lines they all looked fine but there is a loud hissing coming from around the upper plenum at idle, it goes away when you open the TB. so i turn it off and change the driver bank plugs, the back 2 had oil, clean oil, in the hole all over the plug, but not the cumbustion chamber, and not on the threads. i checked my oil, it hasnt been leaking and i dont think its burning because my exhaust exits right before my bumber and there is no oil residue on the bumper or in any of the tips. somehow the oil is not even showing on the dipstick. about 2100 miles after the oil change. i put in 6 quarts when i changed it too. there is no oil on the motor other than the 2 plug holes where i found it, and in the number 8 plug under the boot, i found a little metal piece like something that holds the bumper on. after i did all that i let the car sit with the battery disconnected for a bit and started it up. still idles bad and hisses. but no codes after i let it sit for about 2 minutes running. it has idled rough before, but if i hold the gas at about 1100 for a few seconds and let off it will go back to normal. that didnt happen this time. i have an off-road h-pipe and no MIL eliminators but that hasnt been a problem for 2100 miles (about a month) could that be the problem? anyone have any ideas?
 
B

bdcardinal

tree hugger
Jun 10, 2003
3,612
16
69
santa barbara, CA
Aug 10, 2004
#2
  • Aug 10, 2004
  • #2
it is the IAC ( Idle Air Control) solenoid. you can clean it with some throttle body cleaner for a temporary fix, however you will eventually need to replace it.
 

StangLou

Active Member
Jul 9, 2003
1,264
0
36
Holly Springs, NC
Aug 10, 2004
#3
  • Aug 10, 2004
  • #3
The problem does sound like your IAC, but I dont recall ever hearing a bad IAC "hiss" like he is talking about. You can try to clean it, and see if it works I guess. Sounds like you have a vaccum leak somewhere though since you are hearing a hissing sound. Have you done a tb/plenum combo? If so was everything tightened back up correctly???
 
S

scooter6753

New Member
May 11, 2004
101
0
0
maryland
Aug 10, 2004
#4
  • Aug 10, 2004
  • #4
check ur MAF...sounds like its dead....also check to make sure ur filter is on tight and the back end of ur MAF is connected. I just fixed the same problem with mine.
 

KaPPaBaLL

New Member
Nov 28, 2003
1,326
0
0
BAYAREA
Aug 10, 2004
#5
  • Aug 10, 2004
  • #5
clean both of what these people said.
 
9

98laseredgt

New Member
Jul 16, 2004
122
0
0
indianapolis
Aug 11, 2004
#6
  • Aug 11, 2004
  • #6
problem fixed, it was the IAC. the hissing was just the intake i guess, it still does it but all the lines are connected and everything is tight. i also changed the fuel filter and PCV and plugs while i was at it. thanks for the replies guys.
 

new22003

New Member
Jun 22, 2003
657
0
0
Missouri
Aug 11, 2004
#7
  • Aug 11, 2004
  • #7
Wonder if ford will ever fix that damn IAC. Gone out twice on the wifes car already.
 
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