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Smoking on startup after sitting
- Thread starter 4yers
- Start date
The most logical conclusion is that it wasn't the engine that was causing the problem.
But let's diagnose it in a rational manner. We observe oil burning on startup. First check is to make sure it's actually oil other than just condensation from the exhaust. If we can determine it is in fact oil, then we have to ascertain where is the oil coming from?
The oil must be getting into either the combustion chamber or the turbocharger which are the areas of heat likely to cause smoke. If the smoke dissipates upon warm-up, this would tend to suggest to me (especially given the extra information of parking on an incline) a poorly machined or worn out valve guide; probably near the rear of the engine. Another related option is inadequate drainback from the valvespring pocket. As the engine cools down after parking, the oil still in the head/pocket could be making its way down the guide and ending up in in one of the cylinders. Upon startup- you get smoke. This might also explain reports of broken valve springs from one of the original posters or the 2.7 Nano reports. The finger followers on the ST/Nano engine rely on the hydraulic guide lifter and the valve guide to keep them in position over the valve stem. Too much valve stem clearance could cause the follower to "pop" the spring retainer- ending up in mechanical breakage.
The other possibility, the turbo could be caused by a bad seal between the turbine and bearing section. This could also be explained via the "parking on incline". When the turbo cools, the clearance to the shaft increases and the gravity acting on any oil within the bearing section would tend to seep into the turbine proper. This would also result in the same smoke on startup.
Those would be my two top culprits. Now, if overall oil consumption is high, we could look at other issues- turbo oil drainback, the lack of a proper oil restriction to the turbo bearings, but these would tend to produce oil consumption and part failures outside of just some smoke after sitting.
But let's diagnose it in a rational manner. We observe oil burning on startup. First check is to make sure it's actually oil other than just condensation from the exhaust. If we can determine it is in fact oil, then we have to ascertain where is the oil coming from?
The oil must be getting into either the combustion chamber or the turbocharger which are the areas of heat likely to cause smoke. If the smoke dissipates upon warm-up, this would tend to suggest to me (especially given the extra information of parking on an incline) a poorly machined or worn out valve guide; probably near the rear of the engine. Another related option is inadequate drainback from the valvespring pocket. As the engine cools down after parking, the oil still in the head/pocket could be making its way down the guide and ending up in in one of the cylinders. Upon startup- you get smoke. This might also explain reports of broken valve springs from one of the original posters or the 2.7 Nano reports. The finger followers on the ST/Nano engine rely on the hydraulic guide lifter and the valve guide to keep them in position over the valve stem. Too much valve stem clearance could cause the follower to "pop" the spring retainer- ending up in mechanical breakage.
The other possibility, the turbo could be caused by a bad seal between the turbine and bearing section. This could also be explained via the "parking on incline". When the turbo cools, the clearance to the shaft increases and the gravity acting on any oil within the bearing section would tend to seep into the turbine proper. This would also result in the same smoke on startup.
Those would be my two top culprits. Now, if overall oil consumption is high, we could look at other issues- turbo oil drainback, the lack of a proper oil restriction to the turbo bearings, but these would tend to produce oil consumption and part failures outside of just some smoke after sitting.
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Background on my issue, our garage is level and it only happens on a cold start. If the car has been sitting for a few hours there is zero smoke. The dealer blamed it on the Thermal exhaust said water was accumulating causing the smoke (my smoke is always blue), if that is the case why does it only do it on cold starts? Wouldn't water accumulate every time you shut off the engine?
Now the mufflers used by thermal do not have drain holes and it is very easy to hear the water slosh around, I am planning on drilling some small holes on both ends of the muffler to see what happens.
When the car was at the dealer they checked the cats to see if any oil was pooling and they claim nothing was found, I am leaning towards a turbo seal myself. I installed the exhaust last march and last month the smoke show started.......
@boosted_st I would assume the turbo seals were replaced with the engine?
Another thought I had, many people have commented about the coolant consumption on these engines could that have anything to do with it?
Here is another data point that may or may not have anything to do with this issue, fuel dilution on my engine has been increasing and the viscosity has been thin from the first sample at 1000 miles, this sample was taken around 30k miles.
Now the mufflers used by thermal do not have drain holes and it is very easy to hear the water slosh around, I am planning on drilling some small holes on both ends of the muffler to see what happens.
When the car was at the dealer they checked the cats to see if any oil was pooling and they claim nothing was found, I am leaning towards a turbo seal myself. I installed the exhaust last march and last month the smoke show started.......
@boosted_st I would assume the turbo seals were replaced with the engine?
Another thought I had, many people have commented about the coolant consumption on these engines could that have anything to do with it?
Here is another data point that may or may not have anything to do with this issue, fuel dilution on my engine has been increasing and the viscosity has been thin from the first sample at 1000 miles, this sample was taken around 30k miles.
They don't replace "turbo seals". They replace the entire turbocharger. I posted earlier about probable causes for OIL burn on startup. If you live in a high humidity environment (like Houston), you are going to get condensation and combined with unburned hydrocarbons may seem to be oil burning.
There are several people posting- one about water being heard "sloshing" around, (that seems pretty obvious), some about the amount of time their vehicle was parked, some about it seeming to come from only a single side. In most cases, this is easily explained by condensation. If you don't understand how that happens, it's because the hotter the air is- the more moisture it can absorb. As the medium (exhaust system) cools down, the moisture in the air condenses into liquid in the exhaust system. Upon startup, the heat will begin the evap process. The result: something that looks like cold start oil burning problems.
If the visible emissions start immediately upon a true "cold start"- and I mean immediately upon startup before the exhaust has a chance to warm up, you're looking at something more likely in the combustion chamber since it's going to get hot faster than any other part. Which leads back to valve guides or another possibility: some type of head gasket problem. The clearance as the vehicle cools down could result in coolant seepage into the combustion chamber such that when the vehicle is restarted the coolant ends up being burnt in the combustion chamber. Of course, this isn't an oil issue, but it's possible to be mistaken for one. Head gasket problems could be diagnosed by oil traces in the coolant reservoir tank or consumption of coolant.
I listed the two primary reasons that would actually result in oil burning conditions in my last post. Bottom line- if you want someone to help diagnose problems over the internet you need to supply more accurate observations. But, I understand your frustration- the local tech is not only constricted to actual experience, but by his service manager as to what Ford will pay for profitably.
There are several people posting- one about water being heard "sloshing" around, (that seems pretty obvious), some about the amount of time their vehicle was parked, some about it seeming to come from only a single side. In most cases, this is easily explained by condensation. If you don't understand how that happens, it's because the hotter the air is- the more moisture it can absorb. As the medium (exhaust system) cools down, the moisture in the air condenses into liquid in the exhaust system. Upon startup, the heat will begin the evap process. The result: something that looks like cold start oil burning problems.
If the visible emissions start immediately upon a true "cold start"- and I mean immediately upon startup before the exhaust has a chance to warm up, you're looking at something more likely in the combustion chamber since it's going to get hot faster than any other part. Which leads back to valve guides or another possibility: some type of head gasket problem. The clearance as the vehicle cools down could result in coolant seepage into the combustion chamber such that when the vehicle is restarted the coolant ends up being burnt in the combustion chamber. Of course, this isn't an oil issue, but it's possible to be mistaken for one. Head gasket problems could be diagnosed by oil traces in the coolant reservoir tank or consumption of coolant.
I listed the two primary reasons that would actually result in oil burning conditions in my last post. Bottom line- if you want someone to help diagnose problems over the internet you need to supply more accurate observations. But, I understand your frustration- the local tech is not only constricted to actual experience, but by his service manager as to what Ford will pay for profitably.
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I've got the same issue with mine. It's a 2021 ST that was built in Sept. of 2021. - only 9K miles on it. The smoke varies in intensity depending on the day, but it's blue-colored and smells like burning oil to me. Always heaviest from the drivers side muffler. I've been to two different dealers for a "diagnosis". The first dealer claimed it was condensation in the catalytic converters, but candidly didn't really take the time to diagnose anything.
In the case of the second dealer, I parked it in their lot overnight and brought the service writer and tech out to the parking lot with me the next morning witness the issue. They agreed that it was oil burning, but had to open a case with the Ford hotline to get guidance on how to proceed. They gave me the vehicle back and said "keep the oil topped off until we get a fix". It's been nearly two weeks and still nothing from Ford on what to do. I've not noticed any measurable oil consumption, nor is there any coolant loss or evidence of contamination with oil.
Seems like they could pull it in the shop, pull the plugs out, let it set overnight, and put a bore scope down the cylinders the next morning to figure out if oil was leaking down from the head...assuming it's enough to even see on camera. Supposed to get an update on Monday, so we'll see where they decide to go with this.
In the case of the second dealer, I parked it in their lot overnight and brought the service writer and tech out to the parking lot with me the next morning witness the issue. They agreed that it was oil burning, but had to open a case with the Ford hotline to get guidance on how to proceed. They gave me the vehicle back and said "keep the oil topped off until we get a fix". It's been nearly two weeks and still nothing from Ford on what to do. I've not noticed any measurable oil consumption, nor is there any coolant loss or evidence of contamination with oil.
Seems like they could pull it in the shop, pull the plugs out, let it set overnight, and put a bore scope down the cylinders the next morning to figure out if oil was leaking down from the head...assuming it's enough to even see on camera. Supposed to get an update on Monday, so we'll see where they decide to go with this.
@tjrigario
A couple of things to look at: When you took it to the second dealer was the smoke visible immediately after startup? Or did it take a minute or so? You say that the amount of smoke was "depending on the day". Are your drives mostly short hauls to work or back where things might not come entirely up to operating temps? I doubt that even any type of bore scope would detect any problem so that's a non-starter. Try this- take it on a long highway run for at least 15-20 minutes so it comes completely up to temp. Bring it home and shut it down for at least 3-4 hours. Then start it up. Do you see smoke immediately? Does it begin after a minute or so? Is it more or less intense than what you've noticed? Let us know results.
A couple of things to look at: When you took it to the second dealer was the smoke visible immediately after startup? Or did it take a minute or so? You say that the amount of smoke was "depending on the day". Are your drives mostly short hauls to work or back where things might not come entirely up to operating temps? I doubt that even any type of bore scope would detect any problem so that's a non-starter. Try this- take it on a long highway run for at least 15-20 minutes so it comes completely up to temp. Bring it home and shut it down for at least 3-4 hours. Then start it up. Do you see smoke immediately? Does it begin after a minute or so? Is it more or less intense than what you've noticed? Let us know results.
@TMac
Yeah, the smoke is ALWAYS immediately after startup and then clears up after a few seconds. My wife primarily drives the Explorer and she's driving primarily short trips (at least 30min), but long enough for it to get to full operating temp. I've never once seen it smoke unless it completely cold soaks overnight.
As far as intensity - from what I can tell, it doesn't seem to be impacted by driving time and/or intensity. At the dealer, it was noticeably less smoke than it was today when I started it up in the morning. Nothing in terms of driving habits/distance has changed since that visit.
Yeah, the smoke is ALWAYS immediately after startup and then clears up after a few seconds. My wife primarily drives the Explorer and she's driving primarily short trips (at least 30min), but long enough for it to get to full operating temp. I've never once seen it smoke unless it completely cold soaks overnight.
As far as intensity - from what I can tell, it doesn't seem to be impacted by driving time and/or intensity. At the dealer, it was noticeably less smoke than it was today when I started it up in the morning. Nothing in terms of driving habits/distance has changed since that visit.
Update as of today....
Explorer is going back in for some "diagnostic" on Monday of next week. First step is to check the PCV system for signs of trouble there. They will also be looking into the intake to see if there's any pooling of oil. Depending on what they find, it could be a PCV valve and/or valve stem seal replacement. We'll see what they find!
Explorer is going back in for some "diagnostic" on Monday of next week. First step is to check the PCV system for signs of trouble there. They will also be looking into the intake to see if there's any pooling of oil. Depending on what they find, it could be a PCV valve and/or valve stem seal replacement. We'll see what they find!
