Soot Covered O2 Caused By Oil Leak in Turbo?
#1
Senior Member
Thread Starter
Soot Covered O2 Caused By Oil Leak in Turbo?
After chasing performance issues for years wondering if this is plausible? Drivers side o2 is black, passenger side clean. Checked plugs and they were perfect. I figured if it were running rich drivers side plugs would be black, but not the case. All I can come up with is exhaust side of Turbo leaking oil coating the o2 and causing issues. Actually got a code for drivers side o2, replaced it and 3 days later, black again. Drivers side Turbo housing has oil on it. Truck seemed to run better right after o2 replacement and has gone down hill again after a couple months.
Best way to figure out if oil is leaking into exhaust from Turbo? Would the o2 be wet from oil, or would it be just sooty because of the heat?
126,000 miles on my truck. I do have the start up rattle but I really don't think it has anything to do with it, no one seems to have as drastic performance issues as I do because of the rattle.
Trying to figure out if I pay for the tsb, or pay to replace that turbo
Best way to figure out if oil is leaking into exhaust from Turbo? Would the o2 be wet from oil, or would it be just sooty because of the heat?
126,000 miles on my truck. I do have the start up rattle but I really don't think it has anything to do with it, no one seems to have as drastic performance issues as I do because of the rattle.
Trying to figure out if I pay for the tsb, or pay to replace that turbo
#2
My truck just threw a code for catalyst efficiency on bank 1. I have had a coolant loss over the past couple of the months without visibly finding where its going. The dealer said the passenger side turbo was leaking so I paid them to replace it however 2 months later I am still losing coolant. I'm pulling plugs tomorrow.
#3
Senior Member
Thread Starter
Its definitely not coolant in mine. I think its oil but I haven't been able to figure it out for sure. To me it makes sense as the sensor would get clogged up/not read as fast and read less oxygen in the exhaust, cutting fuel and making that side run leaner. Which kind of matches up with the O2 readings I am getting...drivers side runs leaner than passenger side. If it was a rich fuel mixture I would imagine the plugs would be covered in soot but they are perfect.
The other reason I am thinking lazy o2 sensor caused by oil is as you go up in gears/rpm, the o2 readings on both sides get closer together and the truck feels better in higher gears, like it finally is getting proper readings from the o2 sensor but it takes a few seconds. Down low, when it shifts to second gear it will blow off all the boost and only stay in 2nd gear for a short time, quickly trying to go up in gears. Its weird it does not like being in 1-3 at all.
I was thinking clogged cat on the drivers side as well was a possibility, especially given the known issues with the cats, but less than a year ago I did a back pressure test and was getting below 2 psi back pressure on both sides.
I don't trust the dealer to try and diagnose this given their past history, and since I am paying for everything do not want to play the guessing game.
I am going to pull sensors again tonight possibly and try to pull the piping off the turbo and see what I can see.
The other reason I am thinking lazy o2 sensor caused by oil is as you go up in gears/rpm, the o2 readings on both sides get closer together and the truck feels better in higher gears, like it finally is getting proper readings from the o2 sensor but it takes a few seconds. Down low, when it shifts to second gear it will blow off all the boost and only stay in 2nd gear for a short time, quickly trying to go up in gears. Its weird it does not like being in 1-3 at all.
I was thinking clogged cat on the drivers side as well was a possibility, especially given the known issues with the cats, but less than a year ago I did a back pressure test and was getting below 2 psi back pressure on both sides.
I don't trust the dealer to try and diagnose this given their past history, and since I am paying for everything do not want to play the guessing game.
I am going to pull sensors again tonight possibly and try to pull the piping off the turbo and see what I can see.
#4
Boost :)
I have worked on turbocharged cars over 15 years now and have blown my fair share of turbos. I would be surprised if it was an oil issue with the turbo.
First and foremost, oil doesn't leave a black residue usually. Most often times it will leave the O2 grey and chalky looking.
Generally if a seal goes, then the play in the turbo itself will increase. You can of course check that from the back or front of turbo whichever is easier to get access to. In your case it might be the back because you could inspect the turbine and wastegate housing for signs of leak there too.
Easiest way to tell if it is an issue is if there is ANY play in the turbine wheel from front to back. In other words try to grab the center nut and push it out the front of the turbo and then pull it out the back. There should be side to side movement as the floating bearing will not be pressurized with the truck off. However, there should never be any front to back.
You mention being able to view the O2 readings. Do you have a way to view fuel trim as well? The Torque app I believe can do it if you aren't already using it. Usually it will have a Bank 1 and Bank 2 fuel trim. That might help as well in seeing what it is delivering over there versus the other side.
That's just quick off the top of my head. I'll be happy to offer more if you are interested
First and foremost, oil doesn't leave a black residue usually. Most often times it will leave the O2 grey and chalky looking.
Generally if a seal goes, then the play in the turbo itself will increase. You can of course check that from the back or front of turbo whichever is easier to get access to. In your case it might be the back because you could inspect the turbine and wastegate housing for signs of leak there too.
Easiest way to tell if it is an issue is if there is ANY play in the turbine wheel from front to back. In other words try to grab the center nut and push it out the front of the turbo and then pull it out the back. There should be side to side movement as the floating bearing will not be pressurized with the truck off. However, there should never be any front to back.
You mention being able to view the O2 readings. Do you have a way to view fuel trim as well? The Torque app I believe can do it if you aren't already using it. Usually it will have a Bank 1 and Bank 2 fuel trim. That might help as well in seeing what it is delivering over there versus the other side.
That's just quick off the top of my head. I'll be happy to offer more if you are interested
#5
Senior Member
Thread Starter
I have worked on turbocharged cars over 15 years now and have blown my fair share of turbos. I would be surprised if it was an oil issue with the turbo.
First and foremost, oil doesn't leave a black residue usually. Most often times it will leave the O2 grey and chalky looking.
Generally if a seal goes, then the play in the turbo itself will increase. You can of course check that from the back or front of turbo whichever is easier to get access to. In your case it might be the back because you could inspect the turbine and wastegate housing for signs of leak there too.
Easiest way to tell if it is an issue is if there is ANY play in the turbine wheel from front to back. In other words try to grab the center nut and push it out the front of the turbo and then pull it out the back. There should be side to side movement as the floating bearing will not be pressurized with the truck off. However, there should never be any front to back.
You mention being able to view the O2 readings. Do you have a way to view fuel trim as well? The Torque app I believe can do it if you aren't already using it. Usually it will have a Bank 1 and Bank 2 fuel trim. That might help as well in seeing what it is delivering over there versus the other side.
That's just quick off the top of my head. I'll be happy to offer more if you are interested
First and foremost, oil doesn't leave a black residue usually. Most often times it will leave the O2 grey and chalky looking.
Generally if a seal goes, then the play in the turbo itself will increase. You can of course check that from the back or front of turbo whichever is easier to get access to. In your case it might be the back because you could inspect the turbine and wastegate housing for signs of leak there too.
Easiest way to tell if it is an issue is if there is ANY play in the turbine wheel from front to back. In other words try to grab the center nut and push it out the front of the turbo and then pull it out the back. There should be side to side movement as the floating bearing will not be pressurized with the truck off. However, there should never be any front to back.
You mention being able to view the O2 readings. Do you have a way to view fuel trim as well? The Torque app I believe can do it if you aren't already using it. Usually it will have a Bank 1 and Bank 2 fuel trim. That might help as well in seeing what it is delivering over there versus the other side.
That's just quick off the top of my head. I'll be happy to offer more if you are interested
Thank you, yes drivers side fuel trims are running leaner than the passenger side. So passenger side is getting more fuel but the o2 sensor is clean. Assuming the soot on the o2 is causing slow/wrong readings of oxygen transfer and the ECU is sensing it is running rich, so its pulling fuel. But it actually isn't running rich at all from what I can tell. Plugs are perfect, no soot on them, but no sign of running overly lean either. I know its not necessarily a given, but usually if its running rich plugs on that bank would have some carbon on them.
I just don't see another option besides the turbo leaking oil? Unless the cat is plugged up but like I said, I did a back pressure test last Winter and everything looked OK.
Where else would all this excess soot be coming from? Or am I looking at this wrong and the passenger side is actually the messed up side because the sensor is clean?
At least I'm better off than I have been the last 2 years. Before I had no idea what to look at/what was wrong. At least now I know one side is covered in soot and the other clean
#6
Senior Member
Thread Starter
Trending Topics
#8
Senior Member
Thread Starter
Only other thing I am curious about is timing/start up rattle. But I would expect if the timing were off, the plugs would show it. And those plugs look good
#9
Senior Member
Thread Starter
Anybody see a clogged cat causing the o2 to become soot covered like that? This is the drivers side where in the early TSB's they were supposed to get replaced if you had a code due to the water ingestion. Mine never threw a code but I had the water ingestion multiple times. Possible? I did do a back pressure test but maybe I can't get enough airflow going through the system brake boosting to show it being clogged? I also ran stock a while and no codes thrown for the converter...but I don't really trust that because my truck never throws codes
#10
One Clean Machine
iTrader: (5)
Hope you get it figured out man...