Exhaust Leak At O2 Bung

fredfifty

5 Year Member
Nov 23, 2011
320
60
59
SF Bay Area
Whats up with this....is oily fluid (perhaps condensation and grease or something) leaking from what looks like the base of the O2 sensor bung, normal? Im gathering the bung needs to be re-done. But is the oily crap coming out of it normal? Its just the driver side. Whats the diagnosis guys? Thanks!
 

Attachments

  • Sponsors(?)


General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
17,302
5,588
193
polk county florida
I see a wet spot above the 02 sensor on a header tube, that much fluid coming from around the 02 bung would cause that sensor to malfunction, I thing you have a leak above that.
Just my observation.
 
  • Like
Reactions: Mstng93SSP

fredfifty

5 Year Member
Nov 23, 2011
320
60
59
SF Bay Area
T
Your dipstick is popped out of the block and spraying fluid on the header above and the pipe below.

See that ridge on the dipstick tube? That's supposed to seat against the block. I see fluid also on the clutch cable.

9e72d4c7-171f-4a1c-8fc3-190f8abaf96a-jpeg.595511.jpg
so it needs to sit right at that ridge? if so, it came out alot...but i dont see any change in position of the dipstick from up top.
 

fredfifty

5 Year Member
Nov 23, 2011
320
60
59
SF Bay Area
FF37B747-B2E2-4ECD-96EF-69EA3245DC69.jpeg
27EBE8A4-A24B-4771-9436-D9A5C61C4BFB.jpeg
Oil dipstick tube is okay, not leaking oil there. However, further up, just under the header flange area, there is a leak. I checked the header bolts and tightened them, pulled the #8 plug out and it is wet with fuel. I also ran the car without the #8 plug wire and it ran the same. And what could cause the soupy fluid to come out the exhaust? Valve cover gaskets are fine. Any other opinions on what i could be facing?
 

fredfifty

5 Year Member
Nov 23, 2011
320
60
59
SF Bay Area
C3C8017B-97F3-4528-ACFA-8F847DA9D42E.jpeg
2ADC4267-3BCD-4DF5-8807-3B7FD5255822.jpeg
8F5563B3-2C49-4322-927A-6DAEBF6ED75A.jpeg
Looking at the pics, could that really be a HG leak? The wetspots in the pic are around the the #8 cylinder/header area. The head bolt on the end near #8 is wet and so is the area around it which is above where the head and block meet. Could a leak affect that area, above the HG? Im hoping its a valve cover leak. Still doesnt explain the cream comin out the exhaust...im stumped. HG cost quoted was 2000-2500 geezus.
 

Steel1

Mustang Master
Aug 18, 2017
1,060
466
113
50
Connecticut
I would suspect head gasket, valve cover leak wouldn't blow milkshake out the exhaust.
Like mentioned above try to confirm with testing. If your mechanically inclined it's really not
that difficult to replace on these engines, just a lot of nuts and bolts.
 
  • Like
Reactions: fredfifty

JMGlasgow

Mustang Master
Feb 19, 2017
670
333
93
39
That milkshake coming out if your exhaust is definitely signs of a head gasket or cracked head. Pull the head and find the cause. You'll more than likely have to replace that o2 sensor as well.

My 2000 Ranger cracked it's heads (yes both of them) and the engine oil looked just like that stuff coming out of your exhaust. It also came out of the exhaust, and flooded the intake through the ccv tube after the crankcase filled with coolant. I rebuilt the engine as a result, and the damage happened with minutes.
 
  • Like
Reactions: fredfifty

fredfifty

5 Year Member
Nov 23, 2011
320
60
59
SF Bay Area
driver side header with raw oil, passenger side looks okay (dry side)

im assuming a piston ring or valve seal failure...have not done compression or engine block test. is it safe to assume the creamy crap coming out is oil and condensation? not a BHG

0CF9C920-3D74-41C2-9356-0921F6C82374.png 8B3170B9-FB9C-4F7D-88A6-992199592C7C.png
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
17,302
5,588
193
polk county florida
At this point does it matter? Heads gotta come off anyway. Looks like a rebuild to me. I dought condensation that close to the header would have a place to mix with the oil. Compression test will reveal alot.
 

fredfifty

5 Year Member
Nov 23, 2011
320
60
59
SF Bay Area
At this point does it matter? Heads gotta come off anyway. Looks like a rebuild to me. I dought condensation that close to the header would have a place to mix with the oil. Compression test will reveal alot.
wishful thinking that valve seals are worn then i would only have to pull the valve covers and upper. but youre right..doesnt really matter.
 
Thread starter Similar threads Forum Replies Date
K Help P1151 SN95 V6 Mustang Tech 1
SmokeytheFox 5.0 leaking out oil Fox 5.0 Mustang Tech 12
S Help Leaking manifold 2005 - 2014 S-197 Mustang -General/Talk- 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
L Water pooling under seats 1996 - 2004 SN95 Mustang -General/Talk- 0
ragtop88 Engine Rear Engine Oil Leak Fox 5.0 Mustang Tech 6
R Engine Smoke test for possible leaking lower intake gasket Fox 5.0 Mustang Tech 0
91GTstroked Engine Lower intake vacuum leak Fox 5.0 Mustang Tech 7
8 Coolant leak Fox 5.0 Mustang Tech 4
R Passenger side leak issues and cowl questions 1996 - 2004 SN95 Mustang -General/Talk- 1
T No power to the MAF Sensor 1996 - 2004 SN95 Mustang -General/Talk- 0
H 93 302 BBK Header Gasket Leak 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 8
A Suspension Fox steering rack leaking need help Fox 5.0 Mustang Tech 1
J Temp sending unit leak? Fox 5.0 Mustang Tech 1
B 1982 Mustang 5.0 oil leak Fox 5.0 Mustang Tech 3
B Engine Questions regarding a 93 Cobra Vacuum Leak/Intake Manifold Fox 5.0 Mustang Tech 6
E Help my 02 GT is leaking something!? SN95 4.6L Mustang Tech 2
fredfifty Engine Low Oil Sensor Gasket Leak Fox 5.0 Mustang Tech 2
W Drivetrain T5 Input Shaft - Will it leak ? Fox 5.0 Mustang Tech 0
T Help - Leak Conv. Window! 2005 - 2014 S-197 Mustang -General/Talk- 0
A C4 Transmission kick down shifter is leaking Classic Mustang Specific Tech 12
S Leaking '89 5.0 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 12
T Rack and pinion Leak 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 4
T Heater Core fix 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 21
L 2000 GT Head Gasket - Leaking Coolant; mileage = 71,000ish 1996 - 2004 SN95 Mustang -General/Talk- 1
D Help! Mystery oil leak The Welcome Wagon 14
W HELP: 2007 Vert Leaking Above Passenger Door 2005 - 2009 Specific Tech 0
trlps_ 02’ Mustang GT flutter like sound 1996 - 2004 SN95 Mustang -General/Talk- 6
E Water leak 1996 - 2004 SN95 Mustang -General/Talk- 4
C Leak in trunk area 2005 - 2009 Specific Tech 1
James V Fox Is it normal to be paranoid your gaskets will leak? 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 19
G leaking 6r80 tansmission 2012 gt 2010 - 2014 Specific Tech 2
0 02 mustang GT leaking coolant after head gasket job... 1996 - 2004 SN95 Mustang -General/Talk- 1
D Engine 94 5.0 strange oil leak 1994 - 1995 Specific Tech 7
91GTstroked Engine Coolant leak by water pump Fox 5.0 Mustang Tech 12
J Exhaust Possible Exhaust Leak Diagnosis? Fox 5.0 Mustang Tech 5
H 2003 Mustang GT 4.6L Intake Manifold leak SN95 4.6L Mustang Tech 0
K Fox Coolant Leaking 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 7
86ESSR Exhaust Leak at collector, AFR misread 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 5
sigsterrr Engine Water pump leak driving me crazy Fox 5.0 Mustang Tech 7
C Rear Diff Leak 1996 - 2004 SN95 Mustang -General/Talk- 4
L Weekend of stop the friggin leaks has begun. 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 12
L A box full of STOP THE DAMN LEAKS arrived 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 22
T 66 A/C - How do I check for leaks before charging 1965 - 1973 Classic Mustangs -General/Talk- 0
J Thermostat Housing- leak that wont stop 1974 - 1978 Mustang II Talk & Tech 19
P Fuel Fuel Leak after replacing fuel filter SN95 4.6L Mustang Tech 4
M Transmission leak 1996 - 2004 SN95 Mustang -General/Talk- 1
Enzio Exhaust exhaust manifold leak 1974 - 1978 Mustang II Talk & Tech 58
T Fuel Barfing Gas at the Track Fox 5.0 Mustang Tech 12
Similar threads