Blue smoke under load

oil
smoke

#1

I have a 2010 lancer evolution, intermittently under light to no acceleration the car emits a large cloud of blue-grey smoke from the exhaust accompanied by noticeable oil consumption. This only happens when in 5th or 6th gear or when it changes from 5th to 6th. It only seems to happen when accelerating onto the highway or when going up an incline in a high gear. It only ever lets out smoke when under 2500rpm, never above 2500 and only for a second or two. if I downshift to 5th while this is happening, it stops. I’m at a loss as to why its burning oil.


#2

Sure sounds like the piston rings are getting worn or possible valve guides?


#3

Your turbo charger is leaking oil into the exhaust.


#4

The turbo has low miles, besides, the smoke only happens when out of boost, never after boost or while in boost.


#5

All I can say is Nevada is seldom wrong.


#6

Boost has little to do with a turbocharger leaking oil. Oil is pumped to the turbo charger bearing while the engine is running. When this become worse you may see an oil smoke cloud during a hot restart.

Mitsubishi’s during the 1980’s had an oil separator in the PCV system that can be the cause of this but I don’t believe any modern turbos have this.


#7

If the car were mine I’d run a dry/wet compression test or leakdown test. There needs to be a determination as to whether there’s a ring issue as that could influence a lot of decisions; as in major repair money or even trading the car off.


#8

Nevada sounds right, typical symptoms of a leaking turbo, leaking into the exhaust stream after the engine. There is constant oil pressure and flow to the turbo whenever the engine is running.

I’d bet if you pulled the spark plugs there would be little or no indication of oil fouling in the cylinders.


#9

Burning oil was never seen during restarts. Compression test yielded low compression in cylinder 4. The excessive blowby and crankcase pressure was forcing oil past seals. It wasn’t due to a worn turbo at all. Besides if it was a worn turbo leaking into the exhaust it wouldn’t cause a huge loss of power to the point of nearly stalling like what I had. Also It wouldn’t be such a rare occurrence. I’m taking once in a rare while a huge cloud of smoke pours out for two seconds then stops instantly and won’t smoke at all ever agin for another few hundred miles or so. Another thing, plug #4 was fouled worse than the others. The engine is being rebuilt this week.


#10

The turbo is fine, the engine needs to be rebuilt, that’s a relief. Looks like Bing was right this time (or fairly close).

It seems unusual for a six year old engine to have piston problems but Hyundai, Subaru and Toyota are also experiencing piston/ring problems. I say piston problems because the replacement pistons have been redesigned so that the ring groves don’t become clogged with carbon.

So who pays for this repair? This is somewhat expensive.


#11

The previous owner didn’t have the car tuned properly I suspect that was the cause, because you really don’t hear about rings going on evos. I am unfortunately paying out of pocket, new pistons, rings, gaskets and a new timing chain.


#12

Your car is a good example of why I made the suggestion earlier about a compression test.

Regarding ring jobs (and I know this may sound negative) is that it’s very easy for a ring job to go south quickly.

There’s a hone the cylinders, slap a set of rings on the pistons, and send it on its way method.

There’s a mike the cylinders and inspect every piston ring land during ring installation for proper fit method along with a very careful inspection of the cylinder walls after honing; assuming the cylinders are not tapered or egged badly out of spec.

The former can deteriorate quickly or not function well from the get-go. The latter can turn out well over the long haul.

I would also hope with the ring job that they would mike the crank journals with the rods out. Way out of whack rod journals can lead to problems later on also.


#13
Besides if it was a worn turbo leaking into the exhaust it wouldn't cause a huge loss of power to the point of nearly stalling like what I had. Also It wouldn't be such a rare occurrence. I'm taking once in a rare while a huge cloud of smoke pours out for two seconds then stops instantly and won't smoke at all ever agin for another few hundred miles or so.

I would ask the same question about worn rings on one cylinder.

I’d say this saga isn’t over yet…


#14

My 2 cents worth. Blue smoke under load, almost always worn or sticky rings. Blue smoke when taking foot off the gas at highway speed, usually valve guide seals.

Proper compression check will reveal the cause.


#15

I concluded it was the rings, valves were perfect as well as the turbo. The smoke was caused by the excessive crankcase pressure forcing oil past seals. So yes the saga is over and its been fixed.