• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Idle stop screw question

  • Thread starter Thread starter RacinChris
  • Start date Start date Feb 29, 2004
R

RacinChris

Founding Member
Nov 6, 2000
274
0
16
Gainesville, FL
Feb 29, 2004
#1
  • Feb 29, 2004
  • #1
Hey guys, I'm trying to fix my idle, and I was following these directions on the Corral: http://www.corral.net/tech/maintenance/idlereset.html

I took two pics of this piece, which I think is the idle air bypass solenoid, disconnected and connected. With it disconnected, it idles nicely, around 700 RPMs, so there was no need to adjust the idle stop screw. With it connected, it starts out around 1200 RPMs, and gradually increases to 1500 RPMs, and it doesn't come down. My question is, can I adjust the idle stop screw with this piece connected, or is there something else wrong that needs to be fixed?
 

Attachments

  • P2290005.webp
    81.5 KB · Views: 257
  • P2290006.webp
    59 KB · Views: 236

A-mann

Founding Member
Jun 10, 2001
498
0
0
Delran, NJ
Feb 29, 2004
#2
  • Feb 29, 2004
  • #2
I've never disconnected the air bypass valve to adjust the idle. I just turned the idle adjustment screw till it reads around 800rpms and be done with it.
 
R

RacinChris

Founding Member
Nov 6, 2000
274
0
16
Gainesville, FL
Feb 29, 2004
#3
  • Feb 29, 2004
  • #3
A-mann said:
I've never disconnected the air bypass valve to adjust the idle. I just turned the idle adjustment screw till it reads around 800rpms and be done with it.
Click to expand...

Well, I read somewhere that the engine should be able to idle with it connected and with it disconnected. If you disconnected yours, would it still be able to idle?
 
R

RacinChris

Founding Member
Nov 6, 2000
274
0
16
Gainesville, FL
Feb 29, 2004
#4
  • Feb 29, 2004
  • #4
All right, I adjusted the screw with the air bypass connected, got it to about 800 RPMs. It surges just a little bit until it's warm enough to idle at a constant 800. Then I disconnected the air bypass, to see if it would still idle or not, and it did. There was hardly a difference with it connected/disconnected, whereas before, it would idle way too high. Thanks for the tip.
 
R

RacinChris

Founding Member
Nov 6, 2000
274
0
16
Gainesville, FL
Feb 29, 2004
#5
  • Feb 29, 2004
  • #5
Ok, after driving it for a while tonight, the idle seemed to level off around 1000 RPMs. I tried adjusting the idle stop screw some more, but the RPMs wouldn't go any lower. I also noticed that the throttle seems to stick a little bit now, which is something it never did before (like when I had the air bypass disconneted). Any idea why this is?
 
P

PRO50SC

New Member
Dec 28, 2003
1,012
1
0
Olney, Maryland
Feb 29, 2004
#6
  • Feb 29, 2004
  • #6
Here is a link that should help you. Did you also know that changing your base idle also changes your tps voltage. After adjusting the base idle you will need to set the tps value.
Base idle adjustment

TPS adjustment
 
R

RacinChris

Founding Member
Nov 6, 2000
274
0
16
Gainesville, FL
Feb 29, 2004
#7
  • Feb 29, 2004
  • #7
PRO50SC said:
Here is a link that should help you. Did you also know that changing your base idle also changes your tps voltage. After adjusting the base idle you will need to set the tps value.
Base idle adjustment

TPS adjustment
Click to expand...
Thanks for those sites. I'm gonna try doing that tomorrow.
 
You must log in or register to reply here.

Similar threads

K
2003 GT High Idle, vac leak process
  • krysber
  • May 11, 2025
  • SN95 4.6L Mustang Tech
Replies
2
Views
430
SN95 4.6L Mustang Tech May 11, 2025
krysber
K
H
Hanging idle issues
  • HydraX
  • Mar 22, 2025
  • SVT Tech Forum
Replies
5
Views
528
SVT Tech Forum Aug 4, 2025
squeak93
C
Engine Code 13 and high idle
  • CmdrDerp
  • Dec 14, 2024
  • Fox 5.0 Mustang Tech
Replies
17
Views
800
Fox 5.0 Mustang Tech Dec 21, 2024
manicmechanic007
SURGING IDLE / NO IDLE CHECKLIST FOR 1999–2004 MUSTANG GT (4.6L 2V) - Work In Progress
  • Noobz347
  • Aug 30, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
0
Views
810
1996 - 2004 SN95 Mustang -General/Talk- Aug 30, 2025
Noobz347
Engine 1990 LX 5.0L EFI Mustang Fuel Management Problems - HELP!
  • 5.0LXStanger
  • May 25, 2025
  • Fox 5.0 Mustang Tech
  • 2 3
Replies
45
Views
2K
Fox 5.0 Mustang Tech Jul 11, 2025
5.0LXStanger
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?