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Idle adjustment

  • Thread starter Thread starter cliff88145
  • Start date Start date May 8, 2008

cliff88145

Member
Feb 28, 2006
87
1
18
May 8, 2008
#1
  • May 8, 2008
  • #1
when you disconnect the IAB and adjust the idle screw for your throttle body is the idle speed supposed to stay the same?
The problem I'm having is high idle. My throttle position sensor is set at 1.0v
I installed H/C/I and 70mm TB
 

joel5.0

Member
Jun 15, 2004
429
2
18
Puerto Rico
May 8, 2008
#2
  • May 8, 2008
  • #2
Nope..... BTW, some OEM setups stall when you disconnect the IAB.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
May 8, 2008
#3
  • May 8, 2008
  • #3
You might see an issue where your actual idle is above that of the commanded idle, so your IAC DC is already quite low.

Be sure you dont have any small vac leaks.

Good luck.
 

cliff88145

Member
Feb 28, 2006
87
1
18
May 8, 2008
#4
  • May 8, 2008
  • #4
Thanks guys, I sprayed carb cleaner everywhere on my engine and the idle just sat at 900rpm's so I don't think its a vac leak.
Isn't there a tool to check for vac leaks?
FYI it use to have a bad surge idle till I changed the IAB
 

AnthonyR23

Member
Sep 8, 2006
661
0
16
Ontario
May 8, 2008
#5
  • May 8, 2008
  • #5
Honestly could be a combo of things.... I used to have similar problems.. engine is apart now... but anyways... I found I had to change more than one thing to get back to normal... eg. I replaced what vacuum lines I could get at with a vacuum kit from mustangs unlimited.. different colors to choose... and that improved things a bit.. I also took off the IAC and cleaned it and as much inside the side of the throttle body as I could, I also took off my cold air intake and with one hand held open the tb plate and used a screw driver with a cloth on the end to get some of the sht out. Then checked the tps to make sure it was getting the 5v and that it was below 1v. Think I got to .8. And if you pull off the one vacuum line to the egr valve, it should either stall or sound like it is going to, and if it doesn't change than something is going on with that. I also replaced my tab and tad valves and solenoids with a kit from 50resto.. After all that everything seemed normal.. but I felt like each made an improvement! Good Luck! I would also check your engine error codes.
 

AnthonyR23

Member
Sep 8, 2006
661
0
16
Ontario
May 8, 2008
#6
  • May 8, 2008
  • #6
oh and there is a tool to check vacuum... its a vacuum gauge.. there really cheap!
 
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