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

Slight miss/stumble! Please help!!

  • Thread starter Thread starter Mavrick
  • Start date Start date Aug 12, 2005

Mavrick

Founding Member
Aug 29, 2002
2,264
0
46
Collingwood, ON
Aug 12, 2005
#1
  • Aug 12, 2005
  • #1
My car has a slight miss/stumble i think.. When holding my hand on the intake and observing the motor, it stumbles/jerks once every 3-5 seconds or so. I can also feel air popping out/shooting out of the drivers side tail pipe (shooting a blank), so i think it's on the right bank. When feeling the exhaust, the blanks i feel are not consistant either.

The plugs are canadian tire champion brand copper plugs, gapped at .054" and i just finished replacing the cap+rotor with a good Motorcraft one from my old car, and a new set of Taylor spiro 8mm wires.

I ran the KOER tests and nothing came up in regaurds to the fuel system or anything.. all i got were emissions codes, which i don't think have anything to do with my issue.

All i have done with the fuel system is put in a new 110lph pump, adjustable regulator and gauge. When the car is running i see around 38psi of fuel pressure. The needle jumps up a bit and settles back to 38psi whenever i give it throttle, but doesn't fluctuate or go down at all.

After the car warms up, it seems to run a bit smoother. I can barely feel the miss in my shifter when im looking for it, and even though my car is damn loud right now, you can't hear it unless your really listening up close to the tailpipe.

Also have brand new o2's as of a few days ago...
 

NosPony

New Member
Apr 2, 2004
278
0
0
Canton, Il
Aug 12, 2005
#2
  • Aug 12, 2005
  • #2
For some reason, everytime I have tried champion plugs my car doesnt like them. Try a set of autolite 25s.
 

Mavrick

Founding Member
Aug 29, 2002
2,264
0
46
Collingwood, ON
Aug 12, 2005
#3
  • Aug 12, 2005
  • #3
Alright.. does anyone know where i can find Autolites in Canada? NAPA? Carquest?

Thanks,
 

NosPony

New Member
Apr 2, 2004
278
0
0
Canton, Il
Aug 12, 2005
#4
  • Aug 12, 2005
  • #4
Any parts store should sell them.
 

Mavrick

Founding Member
Aug 29, 2002
2,264
0
46
Collingwood, ON
Aug 12, 2005
#5
  • Aug 12, 2005
  • #5
Went and got some copper autolites... Number 8 plug has oil on it... was afraid of something like this. Blowby? Could it be a headgasket?
 

QDRHRSE

New Member
Dec 31, 2002
1,590
0
0
Palmdale, CA
Aug 12, 2005
#6
  • Aug 12, 2005
  • #6
Only a compression test will tell you that for sure. Look for oil in the radiator, look for oil or dark sludge in the resevoir bottle, water in the oil, greyish smoke from the exhaust.....car running hot, car using water....
 

Mavrick

Founding Member
Aug 29, 2002
2,264
0
46
Collingwood, ON
Aug 12, 2005
#7
  • Aug 12, 2005
  • #7
I'll pick a compression tester up.. any instructions on how i should be using it? With all plugs in, or does that matter?
And just keep the cranks consistant from cylinder to cylinder?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Aug 12, 2005
#8
  • Aug 12, 2005
  • #8
All plugs out. Ignition disabled, Throttle at WOT. Crank till compression levels off.

Do a dry test first and then a wet test right after. the comparison is what is useful [to me].

Good luck.
 

Mavrick

Founding Member
Aug 29, 2002
2,264
0
46
Collingwood, ON
Aug 12, 2005
#9
  • Aug 12, 2005
  • #9
Thats just what i read in my hanes manual. I may try that tonight on a couple cylinders, but i am leaning towards blow-by, as the valve seals are new, and i can't find any oil in my coolant.

I talked to my buddy and we agree'd on $300 for this motor.. 302 lower end .030" over with an e-303 cam in it.. only 7k since rebuild. He'll be helping me put it in etc.. has new headgaskets, intake-to-head gaskets, oil pan gaskets, header gaskets, oil pump pickup tube.. and maybe some other stuff to go with it. I think this is the route that i'm going to take..
 
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