2001 Gt Bullitt Wont Idle Down

Gary L

Active User
Jul 19, 2016
10
0
1
2001 GT Bullitt has 146K miles on it and recently it wont idle down and will sometimes vascilate between 1400 - 2200 rpm it is a 5 speed manual trans and with the engine not idling down it almost like cruise control
 
  • Sponsors (?)


To test with the car running Un plug the iac if there's a difference in idle the it's ok if there's no difference then the iac is bad here's a pic or where it's located
1d3efae347b332eecd85dc3eb0618c73.jpg


Sent from my SM-N910T using Tapatalk
http://cloud.tapatalk.com/s/57939aa7be1d5/bullitt01.jpg
 
To test with the car running Un plug the iac if there's a difference in idle the it's ok if there's no difference then the iac is bad here's a pic or where it's located
1d3efae347b332eecd85dc3eb0618c73.jpg


Sent from my SM-N910T using Tapatalk
http://cloud.tapatalk.com/s/57939aa7be1d5/bullitt01.jpg
thanks much, i did start the car the puled the hose off the air plenum where the iac is attached and the result was a drop of about 400 rpm, based on your comments I am concluding the iac valve is good
 
o.k. thanks for that clarification! Got home from church this a.m. and wanted to implement your suggestion. presently the car wont idle down to less than 1100 rpm, if I shut it down and restart it the rpm will go to 1100 or so and then before I can get around to the plug connection the rpm rises to 1600-1700. sometimes it will vascilate between 1300-1700 rpm. All this being said, disconnecting the electrical plug lead me to an inconclusive result. I dont think I accomplished a valid check of the IAC valve due to the high rpm level
 
From what I understand when you unplugged the iac there was no change in idle speed regardless if it's idling high or not and if so then the iac is bad which controls the idle speed

Sent from my SM-N910T using Tapatalk
 
Hello once again. Yesterday mail brought to me a new IAC valve purchased from RockAuto.com delivered to my mailbo for $53.78. I installed it this a.m. when I first fired the car up again I thought all was well. engine rpm was about right for a cold engine. I then drove the car for some errands and was disappointed to observe that I still have the high idle situation. (morn than 2,000 rpm). I returned home left the engine idling fast and disconnected the electrical plug in and immediately observed a drop in rpm. This causes me to believe the new IAC valve is functioning. any additional suggestions of how I might cure the fast idle?
thanks in advance & God bless, Gary L.
 
IAC Valve (Clean it or replace, also new Gasket), TPS (make sure plug is getting power and try disconnecting it a few times when idling - if idle suddenly shoots up real high, plug it back in it's working - Vac Leaks (Even small ones).