Spark plug diagnostic question

  • Sponsors(?)


90sickfox

I didn't really have an issue with the stink...
SN Certified Technician
Mar 2, 2015
5,178
4,264
203
42
That's a sign of oil being in the combustion chamber....

What cylinder was that and what engine ?
 

CarMichael Angelo

clearly, I’ve got something going on in that hole
15 Year Member
Nov 29, 1999
9,195
6,987
234
62
Birmingham, al
m.imdb.com
5.0 ho out of my 1991 mustang. That was cylinder 5. I figured it was oil fouling, I think its valve seals.
That spark plug looks like its been in the engine for 12000 miles.

It would be wet if it was fouling. It looks to be neither fuel, nor oil. Most likely carbon
Build up.
If the engine eats oil enough to foul a plug, it'd smoke as well I think.
And unless you've either did a leak down test ( preferred) or a compression test to determine overall consistency between cylinders, I'd think twice before pulling anything apart.
 

Hudson N

Member
Aug 7, 2018
50
3
8
Queen creek Arizona
That spark plug looks like its been in the engine for 12000 miles.

It would be wet if it was fouling. It looks to be neither fuel, nor oil. Most likely carbon
Build up.
If the engine eats oil enough to foul a plug, it'd smoke as well I think.
And unless you've either did a leak down test ( preferred) or a compression test to determine overall consistency between cylinders, I'd think twice before pulling anything apart.
She smoked a little. But replaced my PCV and it hasn't smoked much since. Should I put some new plugs in, factory plugs instead of those Bosh plugs the previous owner put in?
 

90sickfox

I didn't really have an issue with the stink...
SN Certified Technician
Mar 2, 2015
5,178
4,264
203
42
Bosch plugs don't like fords....

Change plugs....send it...then check them...
 
Thread starter Similar threads Forum Replies Date
G Fox Spark plug recommendations? 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 8
Sycostang67 Spark plug socket? 2005 - 2009 Specific Tech 5
R Engine Remove the Idiot from the equation. Idle/hesitation issue. Fox 5.0 Mustang Tech 3
T Spark plug gap Fox 5.0 Mustang Tech 3
V 1999 Cobra knocking after spark plug blow out 1996 - 2004 SN95 Mustang -General/Talk- 3
79 Fox Spark plug boot melted. What’s going on? 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 3
93notchback347! What spark plugs do I use with canfield heads and vortech v1 blower Fox 5.0 Mustang Tech 3
Sirocco110 Engine Spark plug wiring confusion. Fox 5.0 Mustang Tech 9
M Forced Induction Spark plug dilemma... Fox 5.0 Mustang Tech 3
S Nitrous Spark Plug help 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 24
X Spark plug gap on 351w Fox 5.0 Mustang Tech 6
H 65 289 spark plug gap/popping! 1965 - 1973 Classic Mustangs -General/Talk- 14
R Spark plugs 1996 - 2004 SN95 Mustang -General/Talk- 2
J Gt40P Heads Spark plug Gap. 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 12
D what spark plugs for 05 GT with Voodoo cams open air tuner magna flow exhaust. 2005 - 2009 Specific Tech 1
A spark plugs 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 8
arnie93lx For Sale Taylor 409 Race-Fit Pro Race Spark Plug Wires Engine and Power Adder 0
3 Spark plugs fowling out Digital Self-tuning Forum 4
A Spark plugs 2005 - 2009 Specific Tech 1
Barron91lx Engine Spark plug wire corona Fox 5.0 Mustang Tech 5
My92cashtrap Engine Spark plug surprise! Fox 5.0 Mustang Tech 2
S Spark plug crossfire SN95 V6 Mustang Tech 4
2 Wet spark plug 1996 - 2004 SN95 Mustang -General/Talk- 0
skiwesser11 Fox Spark plug heat range 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 20
B 99 4.6 2V Misfire (Spark Plugs) 1996 - 2004 SN95 Mustang -General/Talk- 2
S 2006 Mustang GT Premium Spark plugs and coil packs 2005 - 2014 S-197 Mustang -General/Talk- 2
GTVin Engine 94 GT spark plug gap 1994 - 1995 Specific Tech 4
F spark plug gap? 1996 - 2004 SN95 Mustang -General/Talk- 2
A 2006 ford mustang v6 ticking noise coming from engine 2005 - 2014 Specific V6 Tech 1
BlakeusMaximus 2015 GT—What is the correct spark plug gap on these? 2015+ Specific Tech 9
S 2009 Spark plugs 2005 - 2009 Specific Tech 4
1970machwon Engine 1987 5.0 AOD hatchback, weird cylinder heads/ spark plugs question Fox 5.0 Mustang Tech 5
White Wolf 2013 V6 Mustang Spark Plug Question 2005 - 2014 Specific V6 Tech 3
S Best spark plug brand for stage 3 comp cammed 2004 gt 1996 - 2004 SN95 Mustang -General/Talk- 0
T 2005 V6 Spark Plug not threading correctly 2005 - 2014 Specific V6 Tech 0
D Engine 90 5.0 LX Spark Plug wire Fox 5.0 Mustang Tech 0
Sparky714 Forced Induction Spark plugs for supercharger Fox 5.0 Mustang Tech 4
USCGunner Fox spark plugs smell like gas 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 7
D 01 GT Blew Spark Plug Now No Start Fuel Coming Out Exhaust 1996 - 2004 SN95 Mustang -General/Talk- 20
R Spark plug issue 2005 - 2014 S-197 Mustang -General/Talk- 3
E How Do You Know If Your Spark Plug Hole Is Stripped? 2015+ (S550) Mustang -General/Talk 13
S 1997 Cobra Oem Spark Plug Wire Holders 1996 - 2004 SN95 Mustang -General/Talk- 0
9 Spark Plug Wire Touching Bbk Shorty Header Pipe Fox 5.0 Mustang Tech 6
S What's A Good Spark-plug-thread-repair Insert? SVT Tech Forum 8
M Welp, One Of My Spark Plugs Hole Is Stripped.anybody Had A Similar Situation That Could Help? 2005 - 2009 Specific Tech 5
S Spark Plug Blew Out Of Engine Years Ago, Now... SVT Tech Forum 17
USCGunner Spark Plug Question Fox 5.0 Mustang Tech 23
S New Owner Spark Plug Gap Question 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 7
I Socket For Spark Plug SN95 V6 Mustang Tech 0
L Wet Plugs 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 11
Similar threads