• Mustang Forums
  • 1996 - 2004 SN95 Mustang -General/Talk-

2000 GT misfire cylinder 3

  • Thread starter Thread starter TEC2000GT
  • Start date Start date Mar 25, 2021
T

TEC2000GT

New Member
Mar 23, 2021
3
0
1
Charleston, SC
Mar 25, 2021
#1
  • Mar 25, 2021
  • #1
Hey guys, been reading for years but this is my first time posting a question. My 2000 Mustang GT is giving me a code for miss fire on cylinder #3. Engine is a 2003 4.6 2V. No mods. The original coil pack for cylinder 3 was bad. Moved it to cylinder 1 and it coded for cylinder 1. Replaced all 8 coil packs. New spark plugs and boots. All motorcraft. The code for running lean on bank one went away. The cylinder 3 misfire code came back New lash adjusters. Cylinder 3 had a collapsed one. Car is getting bad fuel mileage and it smells like I have a bad cat. Could be fuel getting into the cat. Idles just below 1000 rpms but occasionally it drops to 500 rpms and tries to die. When driving; the car will be running great and out of nowhere, it cuts back. I lose power and then it shoots forward quickly. It does this during acceleration or just cruising at a constant speed. Also, oil pressure is good when running but gauge drops to 0 when idling. I'm using Casterol Synthetic blend. Will have to check the weight but I believe its 5W20.
 

OneSick99GT

Active Member
Nov 20, 2018
364
46
38
Dayton, Ohio
Mar 25, 2021
#2
  • Mar 25, 2021
  • #2
I would have your injectors cleaned. Injectorrx did mine and it was worth the money. I would have the battery and altenator tested and clean the positive and negative terminals. Oil pressure will increase as the rpms increase so no worries there. I would also replace your fuel filter.
 
T

TEC2000GT

New Member
Mar 23, 2021
3
0
1
Charleston, SC
Mar 26, 2021
#3
  • Mar 26, 2021
  • #3
Thank you OneSick99GT. I was thinking fuel injectors but wasn't sure if that would throw the misfire fault. I was thinking of new injectors. I believe the factory injectors are 19psi. Would 24 psi be to much? I am planning on going to flat head pistons, mild cams, and getting the heads worked. So I believe I will need bigger injectors. Is it to early to go with bigger ones? Or do I need to wait?
 

OneSick99GT

Active Member
Nov 20, 2018
364
46
38
Dayton, Ohio
Mar 26, 2021
#4
  • Mar 26, 2021
  • #4
If you swap out to different injectors you will need a tune so the new injector slopes can be adjusted for the 24s. The stock 19s are good enough with what you want to do and your pcm can probably keep you running nice, even if it requires more fuel with your small mods you plan on doing. A tune will cost anywhere from 500 to 700 dollars. So just keep that in mind before changing your injectors. Your car won't run when you upgrade those injectors.so a tune will be mandatory.
 
T

TEC2000GT

New Member
Mar 23, 2021
3
0
1
Charleston, SC
Jun 28, 2021
#5
  • Jun 28, 2021
  • #5
Apologize for late entry. The new injectors solved my issue. The car is running great.
 

OneSick99GT

Active Member
Nov 20, 2018
364
46
38
Dayton, Ohio
Jun 29, 2021
#6
  • Jun 29, 2021
  • #6
I'm glad I could help lead you in the right direction. Enjoy your stang now
 
You must log in or register to reply here.

Similar threads

M
Help! 2003 GT misfire when hot
  • Modular03
  • Feb 10, 2026
  • SN95 4.6L Mustang Tech
Replies
4
Views
310
SN95 4.6L Mustang Tech Feb 13, 2026
Mustang5L5
C
Knocking after pull- went away?
  • Connormcclark
  • Oct 6, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
4
Views
205
1996 - 2004 SN95 Mustang -General/Talk- Oct 6, 2025
gkomo
R
Misfire at high rpm! Help
  • Ryanm2018gt
  • Jan 2, 2026
  • 2015 - 2023 (S550) Mustang -General/Talk
Replies
9
Views
880
2015 - 2023 (S550) Mustang -General/Talk Jan 17, 2026
highplace11
H
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
654
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
801
1996 - 2004 SN95 Mustang -General/Talk- Aug 30, 2025
Noobz347
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1996 - 2004 SN95 Mustang -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?