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

High 2k idle(1988 Mustang GT 5.0 non maf)

  • Thread starter Thread starter BurtHurts75
  • Start date Start date May 28, 2025
  • Tags Tags
    1988 gt 5.0 foxbody idle issues
B

BurtHurts75

Member
May 28, 2025
3
1
13
Nc
May 28, 2025
#1
  • May 28, 2025
  • #1
Ive been scouring the internet to look for this issue, my mustang is idling at 2k rpm

Ive replaced the iac and tps and set them correctly, aswell as setting the idle screw and nothing has changed still idles at 2k

Came to get some help on what this issue could be

(BONE STOCK 88 Mustang GT 5.0)
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,950
10,589
203
polk county florida
May 29, 2025
#2
  • May 29, 2025
  • #2
How long have you owned it?
The vast majority of high idle issues are vacuum related, more so with speed density computers.
 
Reactions: Noobz347

Mcmahst

5 Year Member
Jan 19, 2021
686
270
83
Laguna Woods CA, fort Mohave AZ
May 29, 2025
#3
  • May 29, 2025
  • #3
Maybe check the vacuum at idle?
 
B

BurtHurts75

Member
May 28, 2025
3
1
13
Nc
May 29, 2025
#4
  • May 29, 2025
  • #4
General karthief said:
How long have you owned it?
The vast majority of high idle issues are vacuum related, more so with speed density computers.
Click to expand...
Owned it for about 5 years myself bought it off my grandad. Ill try checking the vacum when I get the time
 
Reactions: General karthief

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,950
10,589
203
polk county florida
May 29, 2025
#5
  • May 29, 2025
  • #5
Pull the upper intake off, I bet a vacuum line is broken under there.
Check them all.
 
B

BurtHurts75

Member
May 28, 2025
3
1
13
Nc
May 29, 2025
#6
  • May 29, 2025
  • #6
General karthief said:
Pull the upper intake off, I bet a vacuum line is broken under there.
Check them all.
Click to expand...
Got it thank you
 
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
476
SN95 4.6L Mustang Tech May 11, 2025
krysber
K
T
Fox 1993 FOX High Idle
  • TheJay806
  • Dec 24, 2024
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2
Replies
37
Views
2K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Jan 15, 2025
Mustang5L5
P
High idle issue and leaking after running.
  • PHoffman
  • Dec 24, 2024
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
1
Views
485
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Dec 24, 2024
General karthief
SURGING IDLE / NO IDLE CHECKLIST FOR 1996–1998 MUSTANG GT (4.6L 2V) - Work In Progress
  • Noobz347
  • Aug 30, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
0
Views
755
1996 - 2004 SN95 Mustang -General/Talk- Aug 30, 2025
Noobz347
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
935
1996 - 2004 SN95 Mustang -General/Talk- Aug 30, 2025
Noobz347
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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?