strange misfire


Dec 26, 2005
Can not figure this one out.I will start the car up drive about 5 minutes and the car will just start missing it will do this for about another 5 minutes and run normal until i shut the car off.I even turned the car off at a redlight and then restarted and it went through the same scenario.It does not matter how long the car sits 5 seconds to 5 hours same thing everytime.It breaks up at idle and everywhere else in the rpm range.If iam driving it starts to breakup if i just mantain speed i will hear and feel it missing then its like a light switch and i feel everything go smooth and run normal.
  • Sponsors(?)


New Member
Feb 11, 2010
Pull codes


2. Check condition and connections for TFI, coil, spark plugs, and grounds
3. Then disconnect the EEC, clean the terminals and reinstall. Check for hole in EGR diaphram.
4. Shake rattle and roll wiring harness at all accessible locations while listening for change.
5. Replace TFI, plug wires, cap and rotor (unless brand spankin new and known to be good). Don't assume spark plug wires are good if they're more than say, a year old (ask me how I know).

Wild Ass guess??? TFI module bad.


Dec 26, 2005
The codes did not come up with anything besides smog equipment junk which has been off since 2000.My original thought was the tfi module but from all the reading i have done they either work or dont.I dont think it is the wires because its like a time clock 5 minutes runs great 5 minutes of missing then run normal till when ever i turn the car off.I will try some of the things you guys have mentioned,thanks for the help


I want to measure mine. It doesn't look that tall.
10 Year Member
Jul 6, 2006
mine did that. was the TFI. Could also be the pickup in the distributor.


Dec 26, 2005
yeah i was going to look at the pick up also.Thanks i will give this stuff a try this weekend and report back


Dec 26, 2005
well it ran good for a few days now the issue is back.Iam thinking it could be the o2 sensors.I drove with them unplugged and the breaking up did not happen.Plugged them back in and it came back.The funny thing is even with the o2s unplugged i do not get a check engine light.I am going to leave them unplugged this week and see what happens.
Thread starter Similar threads Forum Replies Date
5 Strange misfire or sputtering Fox 5.0 Mustang Tech 5
Cort Strange misfire after downshifting 1994 - 1995 Specific Tech 7
EZ123 89 LX stall out and strange idle Fox 5.0 Mustang Tech 9
9 Strange Random Misfire 1994 - 1995 Specific Tech 4
9 strange misfire Fox 5.0 Mustang Tech 14
8 Very strange misfire, Help! Fox 5.0 Mustang Tech 12
Teddyd 1985 fuel pump issue? sounds strange Fox 5.0 Mustang Tech 6
A Strange clutch fork issue SN95 4.6L Mustang Tech 0
screamin gt Strange brake noise, hot front brakes 1996 - 2004 SN95 Mustang -General/Talk- 5
P Drivetrain 1995 GT Auto Transmission Acting Strange 1994 - 1995 Specific Tech 1
S Strange sound coming from under car? 2001 Mustang GT 1996 - 2004 SN95 Mustang -General/Talk- 1
B 2011 - Strange lock / unlock behavior with key fob. 2010 - 2014 Specific Tech 4
B Strange Tail Light Problem 2005 - 2014 S-197 Mustang -General/Talk- 0
S Suspension Strange sound while driving. Sounds like cards in bike spokes. Fox 5.0 Mustang Tech 5
9 Need held, Strange Sound at Ignition Fox 5.0 Mustang Tech 2
N Strange over heating issue. 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 2
D Engine 94 5.0 strange oil leak 1994 - 1995 Specific Tech 7
CHILL347 Suspension Strange 10 way adjustable rear shocks? Fox 5.0 Mustang Tech 9
N Strange question..... SN95 4.6L Mustang Tech 2
F Engine Strange drivability issues and can only pull koeo codes Fox 5.0 Mustang Tech 27
9 Microsquirt with strange cold start problem Digital Self-tuning Forum 5
R Right rear clunk when hitting bumps 2015+ Specific Tech 6
Spooky21 87 LX - strange fuel pump eccentric 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 12
GDawg 1998 GT - fuel gauge strange light SN95 4.6L Mustang Tech 0
Z Strange Noise 1996 - 2004 SN95 Mustang -General/Talk- 2
S Strange Noise Under the Hood Help Needed! 07 Mustang GT 2005 - 2014 S-197 Mustang -General/Talk- 3
V Suspension eibach drag launch and strange shocks Fox 5.0 Mustang Tech 0
W Strange fuel pump issues 1965 - 1973 Classic Mustangs -General/Talk- 1
F 2001 Mustang Cobra - Strange Electrical Problem SN95 4.6L Mustang Tech 5
Calebnc302 03 Gt Strange Problem 1996 - 2004 SN95 Mustang -General/Talk- 0
Jimmy K jam Strange Engine? SN95 4.6L Mustang Tech 1
F Brakes Strange Brake/suspension Noise 1994 - 1995 Specific Tech 4
imp Strange New (to Me) Device 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 0
R Strange Hollow Sound 1996 - 2004 SN95 Mustang -General/Talk- 7
General karthief Strange No Start Condition Fox 5.0 Mustang Tech 16
cmerk27 Engine Very Strange Coolant Leak (checked All The Basics) And Other Problems SN95 4.6L Mustang Tech 21
D Strange Struts 4cyl Or V8 Spindles Fox 5.0 Mustang Tech 11
D Strange Issue 1994 - 1995 Specific Tech 4
N Strange Throttle Body Plenum On 99 Gt SN95 4.6L Mustang Tech 1
W Electrical Headlight Nob Is Acting Strang SN95 4.6L Mustang Tech 2
P Strange Tach Problem 1994 - 1995 Specific Tech 2
D Strange Vibrating Noise 1996 - 2004 SN95 Mustang -General/Talk- 3
I Strange Gurgling Sound In Exhaust SN95 4.6L Mustang Tech 51
T Engine Strange Issue 94 Gt 5spd, Losing Power, No Codes 1994 - 1995 Specific Tech 1
blistovmhz Strange Electrical Gremlins - Ignition 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 27
fox-gt Strange Noise Since 3g Alternator Upgrade Fox 5.0 Mustang Tech 8
lepryy Need Some Help With Turn Signals. Plus A Very Strange Module Found Under My Steering Column. (videos Fox 5.0 Mustang Tech 11
D Electrical Strange Wire In Harness Fox 5.0 Mustang Tech 11
Z Expired Complete Team Z Strip Series 1 Rear End, Strange 10 Way Adjustable Rear Shocks, Upr Torque Boxplates Suspension Parts 6
zhendo95 Strange Knocking Noise Coming From Front End. Help!!! SN95 4.6L Mustang Tech 0
Similar threads