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

Engine Idles at 4000 RPM at start

  • Thread starter Thread starter red5.0fox
  • Start date Start date Dec 1, 2019
Prev
  • 1
  • 2
First Prev 2 of 2
9

90bronco302

New Member
Jun 18, 2024
1
0
1
Louisiana
Jun 18, 2024
#21
  • Jun 18, 2024
  • #21
red5.0fox said:
Just swapped in a 5.0 5 speed engine and tranny, but now everytime we start the car it revs right up to 4000 RPM and stays there. No idea what is causing this problem. We checked the TCP, MAF, salt and peppers, IAC, etc. but still happening. Can anyone help me with this? I have a video, but I can’t post it.
Click to expand...
Did you find a answer to this problem?
 

red5.0fox

Active Member
Dec 1, 2019
190
25
38
Hope Mills, North Carolina
Jun 20, 2024
#22
  • Jun 20, 2024
  • #22
90bronco302 said:
Did you find an answer to this problem?
Click to expand...
If I remember correctly I believe it was the RPM gauge was messed up. Falsely showing 4k rpm
 
Prev
  • 1
  • 2
First Prev 2 of 2
You must log in or register to reply here.

Similar threads

Engine Random Misfire at idle.
  • Gulftown980x
  • Jul 29, 2026
  • SN95 4.6L Mustang Tech
Replies
11
Views
419
SN95 4.6L Mustang Tech Jul 31, 2026
squeak93
F
Fox 1990 Mustang GT 5.0 A9L – Engine suddenly shuts off but immediately restarts when key turned
  • FishermansFriend
  • Aug 9, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
16
Views
493
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Aug 30, 2026
General karthief
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
1K
1996 - 2004 SN95 Mustang -General/Talk- Aug 30, 2025
Noobz347
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
873
1996 - 2004 SN95 Mustang -General/Talk- Aug 30, 2025
Noobz347
T
Help with a 95 5L crank no start
  • TheBubbaJoe
  • Nov 4, 2025
  • 1994 - 1995 Specific Tech
Replies
3
Views
497
1994 - 1995 Specific Tech Nov 5, 2025
AeroCoupe
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?