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

cats smoking

  • Thread starter Thread starter 86mustang5.oh
  • Start date Start date Jul 25, 2005

86mustang5.oh

New Member
Apr 5, 2005
125
0
0
battle creek mi.
Jul 25, 2005
#1
  • Jul 25, 2005
  • #1
if i let my enginve run for about 15 min or if i drove it for that long smoke will start coming out my hood and i found it coming from the forst cat on my exaust its still stock exausht but does any one know why it does this
 

crazypete

All my crevices are greased.
Oct 22, 2004
930
4
18
Arlington, MA
Jul 25, 2005
#2
  • Jul 25, 2005
  • #2
Either:

1. You're running super rich on one side and this causes the converter to heat the heck up in a hurry

or..more likely

2. You're seeping oil down the exhaust pipe.
 

86mustang5.oh

New Member
Apr 5, 2005
125
0
0
battle creek mi.
Jul 25, 2005
#3
  • Jul 25, 2005
  • #3
i kinda smells like oil any ideas how that is happening
 

crazypete

All my crevices are greased.
Oct 22, 2004
930
4
18
Arlington, MA
Jul 25, 2005
#4
  • Jul 25, 2005
  • #4
Either your PCV is blocked and the oil is being squeezed out of the seals or the rear main seal is leaking. Unscrew the oil filler cap and put a dryer sheet over it with a rubber band so crap doesnt fall down into the valve cover and see if after a few warmup cycles it stops smoking. If so, get a push-in breather for the filler stem and you're all set.
 
8

89lxsport50

10 Year Member
Feb 25, 2003
550
5
39
Franklin Tennessee
Jul 25, 2005
#5
  • Jul 25, 2005
  • #5
Are the valve covers leaking?
 

86mustang5.oh

New Member
Apr 5, 2005
125
0
0
battle creek mi.
Jul 25, 2005
#6
  • Jul 25, 2005
  • #6
well if you look at it from the front of the car it is on the rightside of the motor and there is much of anything i`l have to look i geuss
 

86mustang5.oh

New Member
Apr 5, 2005
125
0
0
battle creek mi.
Jul 25, 2005
#7
  • Jul 25, 2005
  • #7
well if you look at it from the front of the car it is on the rightside of the motor and there is much of anything i`l have to look i geuss
and there is no oil cap or anything on that side
 

86mustang5.oh

New Member
Apr 5, 2005
125
0
0
battle creek mi.
Jul 25, 2005
#8
  • Jul 25, 2005
  • #8
valve covers ar not leaking
 

18mustangs

New Member
Jun 8, 2005
533
1
0
Virginia Beach, VA
Jul 25, 2005
#9
  • Jul 25, 2005
  • #9
crazypete said:
Unscrew the oil filler cap and put a dryer sheet over it with a rubber band so crap doesnt fall down into the valve cover and see if after a few warmup cycles it stops smoking. If so, get a push-in breather for the filler stem and you're all set.
Click to expand...

Or maybe he could just replace the PCV filter, grommet and valve and let the system work as it's suppossed to. That'd be about $20 total from 50resto.com One should never run a breather cap on a closed PCV system.
 

86mustang5.oh

New Member
Apr 5, 2005
125
0
0
battle creek mi.
Jul 25, 2005
#10
  • Jul 25, 2005
  • #10
welll i had my dad check it out and well we figured ou t its a exhaust leak off my header and conveinced my mom to get full length .....yay no my stock
 

Foxfan88

My Grandpa has great wood.
Sep 13, 2004
2,487
4
0
Miami, Ok
Jul 25, 2005
#11
  • Jul 25, 2005
  • #11
Is your car automatic?? does it have a tranny leak???
My old 2.3 stang auto used to leak and while driving the fluid would drip on the cats and smoke, it smelt also....
 

kornchild4life

New Member
Mar 30, 2005
46
0
0
islip, ny
Jul 25, 2005
#12
  • Jul 25, 2005
  • #12
Take a look at the oil pan too, make sure the gasket there is all good. I'm having the same problem with the smoke off the cats and exhaust and i think my oil pan gasket is shot...hope im not wrong
 

86mustang5.oh

New Member
Apr 5, 2005
125
0
0
battle creek mi.
Jul 25, 2005
#13
  • Jul 25, 2005
  • #13
no i got a t-5 but yea there is too much oil in my car i cheacekd that gonan have to drain some tomoorw
 
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