3.7 V6 Creamy Oil at rear of Valve Cover & Misfires with DTCs

1970FuryConv

Old Man with a Hat
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Our situation with my wife's 2011 Dodge Nitro 114,000 miles is that it is been running poorly and sometimes refusing to start. Check engine light on. Engine codes are cylinder 3 misfire permanent and multiple cylinder misfire permanent. Removed left side valve cover. I was hoping to see a rocker arm fallen off because of a bad lifter, but unfortunately I didn’t see that.

Valve cover: Has water mixed with oil deposit at rear of valve cover. Looks like brown cream. Otherwise valve cover is clean.

pxl_20210820_215703507ps-jpg.jpg

Rocker arms: still in place. I had my wife turn over the engine while I watched. I could not see any dysfunction of any kind in the rocker arm movement at any of the left side cylinders. This included exhaust and intake valves.

pxl_20210820_215907220ps-jpg.jpg

The block is cast-iron, but the cylinder heads are aluminum. I’m starting to suspect a cracked cylinder head at number 3. Although I don’t understand why that would create a creamy deposit at the back of the valve cover rather than directly above number 3 valves.

My plan was to replace the lash adjusters/lifters for number 3 cylinder. Because there doesn’t seem to be much problem with my current lash adjusters/lifters I’m looking for advice on what might cause the misfires and the brown creamy sludge at the back of the valve cover. The valve cover has no PCV hole, breather hole, or oil cap hole or hole of any kind to let in water from the outside. #3 compression Test 125psi cold. Coolant system pressure test 16psi cold, no pressure loss.

Thanks all members for any advice.
 
Our situation with my wife's 2011 Dodge Nitro 114,000 miles is that it is been running poorly and sometimes refusing to start. Check engine light on. Engine codes are cylinder 3 misfire permanent and multiple cylinder misfire permanent. Removed left side valve cover. I was hoping to see a rocker arm fallen off because of a bad lifter, but unfortunately I didn’t see that.

Valve cover: Has water mixed with oil deposit at rear of valve cover. Looks like brown cream. Otherwise valve cover is clean.

View attachment 482408
Rocker arms: still in place. I had my wife turn over the engine while I watched. I could not see any dysfunction of any kind in the rocker arm movement at any of the left side cylinders. This included exhaust and intake valves.

View attachment 482409
The block is cast-iron, but the cylinder heads are aluminum. I’m starting to suspect a cracked cylinder head at number 3. Although I don’t understand why that would create a creamy deposit at the back of the valve cover rather than directly above number 3 valves.

My plan was to replace the lash adjusters/lifters for number 3 cylinder. Because there doesn’t seem to be much problem with my current lash adjusters/lifters I’m looking for advice on what might cause the misfires and the brown creamy sludge at the back of the valve cover. The valve cover has no PCV hole, breather hole, or oil cap hole or hole of any kind to let in water from the outside. #3 compression Test 125psi cold. Coolant system pressure test 16psi cold, no pressure loss.

Thanks all members for any advice.
I am not familiar with every engine configuration, but generally overhead cam engines do not have lifters. Usually a blown head gasket, cracked head, or broken block gives you a mix of oil and water under pressure and temperature that results in the emulsion you see under your valve cover and/or in the coolant passages and sometimes in the oil in the crankcase. I would think further disassembly is warranted until you can for sure determine the cause.
 
I am not familiar with every engine configuration, but generally overhead cam engines do not have lifters. Usually a blown head gasket, cracked head, or broken block gives you a mix of oil and water under pressure and temperature that results in the emulsion you see under your valve cover and/or in the coolant passages and sometimes in the oil in the crankcase. I would think further disassembly is warranted until you can for sure determine the cause.
My bad. The factory calls them lash adjusters. They look like a lifter with a stem out of the top. The back of the rocker arm rides on the stem. Cam lobes contact roller in the middle of the rocker arm and actuate the valves at the front of the rocker arm where it is over the retainer.

As far as the emulsion, I've never had the valve cover off so I don't know how long it's been there. The valve cover has no breather or PCV. Wondering if water/oil could be from crankcase gases that can't escape.
 
With no ventilation in the valve cover, other than possible windage from the moving items, it might well be that the emulsion you see is from accumulated condensate in the crankcase/head area. How many short trips does the vehicle make where it does not get to full operating temperature for over 10miles at a time?

For multiple missfires and the one constant on #3, I would look at the coil(s) and see if that might be an issue. I started to get intermittent missfires on my 05 Impala 3.4L, which the tech allegedly could not reproduce. This went on for a few service trips! When I was told that all of the missfires were on a particular cyl, I got irate as that was the first time I'd heard that info. After I'd already directed them to replace the spark plugs and the plug wires, the next thing in line was the coils, then the module. So, I directed them to replace the appropriate coil and all was well again. That was at something like 150k miles. When it started again, the other two coils got replaced. End of that issue!

Have the fuel injector functions been investigated? It might be possible to get that done on a diag machine rather than manually having to do them.

Just some thoughts,
CBODY67
 
With no ventilation in the valve cover, other than possible windage from the moving items, it might well be that the emulsion you see is from accumulated condensate in the crankcase/head area. How many short trips does the vehicle make where it does not get to full operating temperature for over 10miles at a time?

That was my first thought about the brown goo. It's pretty common to find that stuff under the oil cap of a short-trip vehicle that doesn't spend enough time at full temp.
 
i would say creamy oil means head gasket or cracked head-------on the 3.9 magnums it is a given....a good mechanic will have a sniffer to detect it....and i wouldnt hang around a mechanic that says he can look at it----either he has the tech or he doesnt-----the looking costs extra every time....
 
Check #3 Fuel Injector. That will Cause a Missfire! I have replaced a Ton of them on That engine

With no ventilation in the valve cover, other than possible windage from the moving items, it might well be that the emulsion you see is from accumulated condensate in the crankcase/head area. How many short trips does the vehicle make where it does not get to full operating temperature for over 10miles at a time?

For multiple missfires and the one constant on #3, I would look at the coil(s) and see if that might be an issue. I started to get intermittent missfires on my 05 Impala 3.4L, which the tech allegedly could not reproduce. This went on for a few service trips! When I was told that all of the missfires were on a particular cyl, I got irate as that was the first time I'd heard that info. After I'd already directed them to replace the spark plugs and the plug wires, the next thing in line was the coils, then the module. So, I directed them to replace the appropriate coil and all was well again. That was at something like 150k miles. When it started again, the other two coils got replaced. End of that issue!

Have the fuel injector functions been investigated? It might be possible to get that done on a diag machine rather than manually having to do them.

Just some thoughts,
CBODY67
  • The truck goes on a lot of short trips to the grocery store and stores near home. My wife doesn't like to drive far if she doesn't have to. Grocery store is 2 miles away.
  • I replaced #3 coil with new NGK. It didn't help.
  • I pulled the #3 lash adjusters this morning. The stems are stiff, no sponginess.
  • I suspect you both are right about #3 fuel injector.
  • I think I'm still going to have a professional shop look at it, because I don't want my wife to get stuck.
 
If the computer has shut down the fuel supply to #3 because of a chronic misfire, that cylinder will probably stay shut down until the code is cleared. Clear the code and see if it repeats. With good compression and a new plug it might fire once the code is cleared. Other obvious choice is a dead fuel injector if the cylinder still won't fire. You can run a hydro carbon test on the cooling system to check for cracks or a bad head gasket. Most auto parts will have a test device that you can rent or borrow.

Dave
 
If I might say, If you had no problem pull out lash adjuster yourself, you should swap injector from the problem cylinder (#3) and swap it to another cylinder , clear the code . and drive it . if the miss fire moved to the cylinder you swap #3 injector to, you found your problem. No cost just time . and change your PCV valve for sludge concern. Short driving causes that not uncommon to see that. Use MOPAR parts .
 
I appreciate the suggestions.
The computer turned off #3 cylinder.
Check engine light started blinking while driving.
Computer was also preventing restart.
Battery Disconnect overnight cleared computer memory, so I got start up in the morning, but I had white smoke/steam billowing out the exhaust pipe. Been happening since problem started.
I had an appointment for Tuesday at a shop I trust.
White smoke clears up after 2 miles of driving, but I dropped the SUV off today. Will let you know what Smith Auto diagnoses.
 
Excessive white smoke from tail pipe, not good. The upper radiator will most likely get rock hard soon after start-up (compression pressurizing coolant system) smoke stops because engine heats up and gasket seals up. Shop will most likely check for combustibles in coolant system. Good luck.
 
Excessive white smoke from tail pipe, not good. The upper radiator will most likely get rock hard soon after start-up (compression pressurizing coolant system) smoke stops because engine heats up and gasket seals up. Shop will most likely check for combustibles in coolant system. Good luck.
· Charles said that they added a chemical to the coolant which changes color when exposed to exhaust gases. The blue color changed immediately to yellow in reaction to CO2 gases from exhaust.

· Pressure in the cooling system: built up in cold engine cooling system on the way from the parking space into the shop. It should not have built up at all. Pressure from cylinder(s) entering cooling system.

· Blown head gasket: when both of the above occur, it indicates a blown head gasket or more serious damage. Both heads will have to be removed and sent off to a machine shop to be magna flux tested and surfaced. Because of the backlog in his work, they will not get to this job for 2 weeks and it won’t be finished for another week after that.

· Estimate: $2000.
Your are right. The reason the white smoke from the exhaust pipe stops after the car warms up is that the gap where the head gasket is blown is closed by metal expansion due to heat. I approved the $2000.
 
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Glad to hear you got your answer. Used cars are crazy money . Probably worth fixing if vehicle is in good shape. I always tell people (customers) "Quality takes time" . Thanks for sharing
 
· Charles said that they added a chemical to the coolant which changes color when exposed to exhaust gases. The blue color changed immediately to yellow in reaction to CO2 gases from exhaust.

· Pressure in the cooling system: built up in cold engine cooling system on the way from the parking space into the shop. It should not have built up at all. Pressure from cylinder(s) entering cooling system.

· Blown head gasket: when both of the above occur, it indicates a blown head gasket or more serious damage. Both heads will have to be removed and sent off to a machine shop to be magna flux tested and surfaced. Because of the backlog in his work, they will not get to this job for 2 weeks and it won’t be finished for another week after that.

· Estimate: $2000.
Your are right. The reason the white smoke from the exhaust pipe stops after the car warms up is that the gap where the head gasket is blown is closed by metal expansion due to heat. I approved the $2000.

Just curiosity, is this a common issue with these engines? I don't know if it's the same engine but I remember the Jeep JK ('07-11) V6 having some common major issues.
 
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