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

Misfiring extremely bad, help!!!!!!!!!!!

  • Thread starter Thread starter BlackFox5.0
  • Start date Start date Apr 5, 2004

BlackFox5.0

Founding Member
Aug 7, 2000
3,514
1
0
Massachusetts
Apr 5, 2004
#1
  • Apr 5, 2004
  • #1
I am getting tired of this. When im cruising, the engine will misfire like nothing I have ever seen before...

I just put an A-trim on, and when just driving normally it misfires like mad now.

Today I gapped my Autolite 25's to .035" and changed my timing to 10* and put 93 octane in the tank. Now it's misfiring really really bad.

I thought maybe it was my MSD so I plugged in the stock one, and it's still doing it, theres no difference...It was doing it before I put the blower on, but it was very distant and a little hard to tell it was happening....

What should I do? I have a brand new cap/rotor too....and FMS wires.

Im guesing it might be because I changed the plug gap?

It started way back when I changed my injectors to 24#'s and a pro-m, it's not the meter because this is my second one....I was told since I was squirting more fuel and didn't have enough spark (stock coil) that would cause the misfire, but I have no idea now

Oh yeah when I was doing the timing I noticed that every now and then the flashing from the timing like would skip like it was misfiring, could it be? How!?
 

BlackFox5.0

Founding Member
Aug 7, 2000
3,514
1
0
Massachusetts
Apr 5, 2004
#2
  • Apr 5, 2004
  • #2
anyone? this is a really serious problem
 
8

85-302

New Member
Dec 18, 2002
74
0
0
st petersburg FL
Apr 5, 2004
#3
  • Apr 5, 2004
  • #3
are you getting conststant spark from all plugs? i would think it could be the coil as you have switched out just about everything else on the ignition side. does it do it all the time and hows the idle? have you had a tune done after you got the A-trim?
 

tomst9

Founding Member
Jun 17, 2002
851
0
0
Bethlehem Pa
Apr 5, 2004
#4
  • Apr 5, 2004
  • #4
maybe you have to run a colder plug. Possibly a autolite 24
 
P

PRO50SC

New Member
Dec 28, 2003
1,012
1
0
Olney, Maryland
Apr 5, 2004
#5
  • Apr 5, 2004
  • #5
tomst9 maybe you have to run a colder plug. Possibly a autolite 24

Agree. I run 23's in mine gapped at .030 and no miss fire.

85-302 are you getting conststant spark from all plugs? i would think it could be the coil as you have switched out just about everything else on the ignition side.

Agree once again. I would try a new coil. I put a Crane Fireball ps91 coil on mine and cured a weird problem I was having with my shift light.

BlackFox5.0 It started way back when I changed my injectors to 24#'s and a pro-m, it's not the meter because this is my second one

What do you mean this is your second one?
I put a 75mm pro-m bullit on mine and the car ran like crap. I took it off and put the stock one on(still runnin' 19's at the time) and it cured the problem. I sent it back and got a refund. Now I run 30's w/ a C&L 76mm mass air w/ no problem.
 
N

noslow5_0

New Member
Nov 7, 2003
422
0
0
dallas tx.
Apr 5, 2004
#6
  • Apr 5, 2004
  • #6
when you checked the timing, did you pull out the pill??? cause i know the computer pulls timing and what not, and with it in, it will skip....
 

BlackFox5.0

Founding Member
Aug 7, 2000
3,514
1
0
Massachusetts
Apr 6, 2004
#7
  • Apr 6, 2004
  • #7
noslow5_0 said:
when you checked the timing, did you pull out the pill??? cause i know the computer pulls timing and what not, and with it in, it will skip....
Click to expand...


I did yes.

PRO50SC, how much boost do you run?

I don't know what saprk plugs to get I'm thinking 23s gapped at .035" which i can get from work today and change them before I come home....
 
C

cjhenry01

New Member
Mar 21, 2004
43
0
0
Apr 6, 2004
#8
  • Apr 6, 2004
  • #8
What do you mean by pulling out the pill? What is the exact & proper way to check timing?
I'm a newbie and can use any help I can get.
Thanks!!!
 
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