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Car feels like it's misfiring all the time, can't diagnose!

  • Thread starter Thread starter BlackFox5.0
  • Start date Start date May 9, 2004

BlackFox5.0

Founding Member
Aug 7, 2000
3,514
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0
Massachusetts
May 9, 2004
#1
  • May 9, 2004
  • #1
I don't know if someone touch my motor at a club meet I went to yesterday, but after I left the show my car was not running right at all.....

Even after the motor was warmed up, the thing ran like crap. If I floored it it would rev, but I could feel it misfiring. Nothing was wrong with it before the show, and I didn't drive hard or anything that would have caused this.

When I just got home from work, I put an ice cube to each exhuast header, and it melted all the same on all 8 of them, so all clyinders are firing.

I checked the plug wires at the plugs, fine, pulled the cap to see if there was water in there, dry....pulled the coil wire off to check if the connection was good, fine.

I did remove my IAB to polish it and it was a dry inside, I didn't bother to clean it since it doesn't really give me problems. Maybe it's sticking? i don't see how that would affect drivability though...

Any suggestions? I need to get this fixed asap, as it really sucks

My timing is at 10* base, Autolite 23's @ .035", 51psi fuel pressure (I was running too lean at 41psi) 36# injectors, 80mm pro-m, 6psi of boost.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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May 9, 2004
#2
  • May 9, 2004
  • #2
Chris, you have hit the big stuff i would have too. have you pulled codes, specifically having done a balance test? if you have a finicky injector, that should help let you know.....
is the MAF clean?
that is all that really comes to mind, other than all the little checks you are doing...good luck bud.
 

BlackFox5.0

Founding Member
Aug 7, 2000
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Massachusetts
May 9, 2004
#3
  • May 9, 2004
  • #3
It seems to act up when the humidity gets up there. How would i clean the MAF? I really don't like touching those sensors in anyway, but I was told to use electrical cleaner. My power pipe pute the meter/filter way down in the fender where it can get went if drivin in the rain, but it's not wet enough for it to get wet at all....

The injectors should be fine, they were flow tested and everything before I got them.....

Never checked for codes.
 

cjones

Founding Member
Jul 20, 2002
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Avondale, AZ
May 9, 2004
#4
  • May 9, 2004
  • #4
have you checked the firing order?? if you think someone messed with your car, it doesn't take long to switch 2 plug wires.
 

BlackFox5.0

Founding Member
Aug 7, 2000
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May 9, 2004
#5
  • May 9, 2004
  • #5
hmm, I just check the firing order, and start from clyinder 1, which is around 1 o'clock if your looking at the engine from the front of the car, the next one should be 3 but it's not....

Which way does the rotor turn counter clockwise? also if anyone has any pics of the distributor with firing order numbers that would help A LOT, i am not home so i don't have my manual with the order/pictures. All i can find is numbers online...

this is the HO order from what I can find: 1-3-7-2-6-5-4-8
 

bmorrisj

Member
Sep 26, 2003
449
0
17
Buena Park, CA
May 9, 2004
#6
  • May 9, 2004
  • #6
rotor turns counter clockwise with #1 at the top.... the cap should have 1 marked....
 

BlackFox5.0

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Aug 7, 2000
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May 9, 2004
#7
  • May 9, 2004
  • #7
OK i was looking at the wire going across the distributor instead of the next plug, lol, opps, anyways my firing order is correct, i noticed one of my plug wires, number 8, drivers side rear plug. The boot was rotated, so i checked it out, and the wire had a cracked spot on it, so I looked closer and the silicone was flaking off! I can see the insulation inside the wire, so I guess thats the problem. it must have hit the header or got really close and cooked it dry. I'll try to see if i have another wire hanging around if not then i'll have to drive home with the bad wire and replace it with another I have at home. I gotta get new wires, the FMS ones i have are just too long
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
May 9, 2004
#8
  • May 9, 2004
  • #8
that sounds good to me (plug wire). although i would be surprised if it is shorting out the spark (does not sound like the wire is that bad, esp if it is not sitting near any metal). but it is normally something funky like that which is the fix.

i dont have MAF, but most use electrical contact cleaner - make sure the can does not spray too hard a stream. and like you said, dont touch the wire with a cotton swap or anything. i think brake cleaner works in a pinch too, but dont do that w/o double checking.

good luck - hope it is something easy.
 

dvs bullet

New Member
Feb 20, 2004
326
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0
Ontario, Canada
May 9, 2004
#9
  • May 9, 2004
  • #9
Also make sure that there is not any moisture in the cap, if you washed the engine before the show it might have got in there, that can cause a hell of a bad idle ( learned from experience lol )
 

BlackFox5.0

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Aug 7, 2000
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Massachusetts
May 10, 2004
#10
  • May 10, 2004
  • #10
Well I changed that plug wire with another of the same brand, just different color. The misfire is not as bad now, but it's still there. If I floor it in first the car still goes, but the power is gone, I mean almost toally gone, and the car still gets loud as if it was normal....this sucks...im gonna chheck the meter after work.
 

jrichker

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Mar 10, 2000
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Dublin GA
May 10, 2004
#11
  • May 10, 2004
  • #11
Dump the codes and see what the computer says is wrong…

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html
 
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