Engine Oil on Sparkplug Threads - Misfiring / Hesitation


New Member
Dec 25, 2018
Alexandria, VA
Hi everyone! This is my first post in this forum. I have been lurking and reading for a while and you have all helped me with my project.

I was checking all my spark plugs the other day and on spark plug # 1 there was oil on the threads and build up on the electrode. I got worried and checked all of the other ones and found oil only on the threads of the others. The other spark plugs had a little bit of black on the side electrode but no buildup or gunk of any sort that would be blocking it. My car was mis firing a few days ago and found this to be a broken distributor wire on #4. I cleaned off all the oil on the spark plugs and put them back in, put new wires in, and fixed the gaps on all the plugs to see if the car was still misfiring or hesitating. Luckily the car stopped mis firing and has not any more since last week. The car is still hesitating on slow acceleration but I think this might have to be something on the carburetor? Im new to this, should I take apart the engine and replace the piston valve seals or something else inside, or should I wait to see if more oil builds up and after I have my carb looked at/fixed?


PS - The car I own is a 1969 Coupe 302ci V8 - with a Holley 4 BBL Carb which still needs to be tuned
  • Sponsors(?)


15 Year Member
Nov 18, 2002
Cape Cod, Ma.
Oil on the plug threads is probably from the valve cover, not from inside the engine. How about starting with a fresh tuneup, plugs, points, condenser, rotor, cap, wires. New filters . Set the dwell and the timing, adjust the carb and see what you have.
Thread starter Similar threads Forum Replies Date
Fastime331 Oil on sparkplug threads, what's the culprit? Fox 5.0 Mustang Tech 17
302mustanglx oil on the treads and tip of my 88 stang sparkplugs Fox 5.0 Mustang Tech 2
EPIK Please Help!!!!97 Cobra sparkplug holes filled with oil??? SN95 4.6L Mustang Tech 8
Asha'man oil in sparkplug holes? 2.3L (N/A & Turbo) Tech 11
C Engine Can’t find oil pressure sensor? 2005 - 2009 Specific Tech 7
M Timing messed up? 2015+ (S550) Mustang -General/Talk 2
V Engine 1990 GT Manual Transmission - Oil Leak and Water plug Fox 5.0 Mustang Tech 8
R 2004 Mustang 3.9L V6 Leaking Fluid or Oil 1996 - 2004 SN95 Mustang -General/Talk- 1
Scott7512 Engine Oil pressure fluctuations Fox 5.0 Mustang Tech 1
Tldeeter 1966 Correct Oil Filter Cap Question Classic Mustang Specific Tech 0
Diesel1277 Engine Oil leak when taking corners hard Fox 5.0 Mustang Tech 3
D Engine Oil in Intake, normal? 1994 - 1995 Specific Tech 15
I Amazing oil disappearing on dipstick trick 1996 - 2004 SN95 Mustang -General/Talk- 4
1 Oil pressure Guage sender question 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 29
M What oil for a 1965 289 1965 - 1973 Classic Mustangs -General/Talk- 6
B Engine Oil pan 1974 - 1978 Mustang II Talk & Tech 1
B Oil pan 1974 - 1978 Mustang II Talk & Tech 5
M mix conventional and synthetic GEAR oil 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 3
woodsnake oil pan clearance with rack and pinion 1965 - 1973 Classic Mustangs -General/Talk- 1
W Engine Oil Change Interval for a car that is not used much ? Fox 5.0 Mustang Tech 13
C 2013 GT low oil pressure at low RPMs or idle 2010 - 2014 Specific Tech 0
SmokeytheFox 5.0 leaking out oil Fox 5.0 Mustang Tech 20
J Fox dipstick not going in all the way 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 9
rdharper02 Engine Need oil whisperer input Fox 5.0 Mustang Tech 15
S197GT ‘06 Mustang GT oil pressure switch?? 2005 - 2009 Specific Tech 1
S 2009 S/C Mod - Oil Leak due to High Crankcase Pressure 2005 - 2009 Specific Tech 1
W Engine 306 oil leaks! Fox 5.0 Mustang Tech 28
ragtop88 Engine Rear Engine Oil Leak Fox 5.0 Mustang Tech 6
S Hello new Mustang owner here The Welcome Wagon 1
A Engine Fuel smell from oil Fox 5.0 Mustang Tech 5
gilzuckie Oil Pressure Gauge swap Classic Mustang Specific Tech 37
J 1965 oil sending unit 1965 - 1973 Classic Mustangs -General/Talk- 22
R Passenger side leak issues and cowl questions 1996 - 2004 SN95 Mustang -General/Talk- 1
W oil pressure gauge jumps 2.3L (N/A & Turbo) Tech 1
B 1982 Mustang 5.0 oil leak Fox 5.0 Mustang Tech 3
79 Fox Engine Been a while since I’ve posted. Oil in coolant. Fox 5.0 Mustang Tech 39
LILCBRA Oil pan gasket change OR starter replacement in a 302 II 1974 - 1978 Mustang II Talk & Tech 11
Red50Fox 8.8 Axle Gear Oil and Modifier Question 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 13
YadiStang Need help with my 1969 oil dipstick 1965 - 1973 Classic Mustangs -General/Talk- 8
fredfifty Engine Low Oil Sensor Gasket Leak Fox 5.0 Mustang Tech 2
ncaruso Metal oil pan for 2018 GT 2015+ Specific Tech 6
HotFox AERA webinars oil, piston coatings and more 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 0
D Oil dip stick tube for 2.3 2.3L (N/A & Turbo) Tech 2
marcelo Engine too much Oil pressure possible ?? Fox 5.0 Mustang Tech 13
N add oil to rear differential in 2001 svt cobra SVT Tech Forum 1
2007_Crown_Vic Engine Oil Level Sensor Fox 5.0 Mustang Tech 7
R Help please. Burns oil, low compression but no broken rings. SN95 4.6L Mustang Tech 1
M Engine Oil temperature gauge? Fox 5.0 Mustang Tech 3
92j3ieje8 How many miles is an oil change needed for a v6 o4 mustang? 1996 - 2004 SN95 Mustang -General/Talk- 0
N Water in oil?? 2010 - 2014 Specific Tech 9
Similar threads