2004 vy blue smoke 128,000k

[somerandom]

My vy v6 is blowing smoke .. not much ,, but sometimes if i give it a quick rev a little notice a little trace of blue smoke,... but it doesn't happen all the time
I did a scan on it when the engine chime came on (and it came up with exhaust sensor)

is it possible at all that it could be an exhaust sensor causing blue smoke? i would have thought if the exhaust sensor is not working correctly it'll be black smoke...

car has only done 128,000k

 

[Greasy Hands]

Did you buy the car new or used ?

Is there any evidence of the car having had a towbar installed in the past ?

mileage seems low, if genuine, to be having oil consumption issues unless its had the absolute **** thrashed out of it. Exhaust sensor will be a symptom of oil consumption, not the cause.

intermittant oil consumption, particularly on over run will probably be valve guides/seals, meaning it needs a headjob (dont we all)

 

[somerandom]

bought the car used,
only within the last 4 weeks i've noticed it... and i don't thrash it at all(not a p-plater )
its not bad, but i guess it'll give me a reason to put a v6 supercharge in it if it gets and worse :-/

it has a towbar installed on it..

can you elaborate on this part pls " Exhaust sensor will be a symptom of oil consumption, not the cause."

 

[Greasy Hands]

towbar being installed explains the low mileage oil consumption - as to what, how often, and how much the engine was thrashed by the person towing with it will forever be a mystery. Every ecotec ive ever seen driving around blowing blue smoke has a towbar installed on it - v8's are meant for that kind of abuse

exhaust sensor malfunction code, in my humble opinion is probably being generated by it being contaminated with oily filth.

untill you transplant the replacement engine in there, you could try running a thicker grade of oil than what your using currently to get by.

BTW, I'm assuming here it definitely is blue smoke and not black.

 

[edals]

A Exhaust Sensor should not cause the Smoke, The Exhaust sensor is called the Oxygen Sensor, This checks the exhaust gases when they are existing, They do gum up after time and start to fail reading, But this causes a spike in fuel economy.
Blue Smoke Generally Indicates Valve Stem seals are worn.
When was car last serviced ? Plugs, Leads, Filters etc done ? A Fouling plug or failing lead could also be a source of the fault.

 

[Sean880]

My vy v6 is blowing smoke .. not much ,, but sometimes if i give it a quick rev a little notice a little trace of blue smoke,... but it doesn't happen all the time
I did a scan on it when the engine chime came on (and it came up with exhaust sensor)

is it possible at all that it could be an exhaust sensor causing blue smoke? i would have thought if the exhaust sensor is not working correctly it'll be black smoke...

car has only done 128,000k

You can easily damage an engine in much less than 100,000 kms if maintenance is neglected. Believe it or not some people believe that you never have to open the car bonnet between scheduled book services and never check oil and other fluid levels for over 10000 kms (except perhaps when a warning light appears on the dash). Then they will skip services or delay having the car serviced way beyond due kms because they think as long as the car runs it is all fine. It is one of the dangers of buying a used car so they need to be checked thoroughly before buying.

Blue smoke obviously means the engine is burning oil so keep an eye on your engine oil levels to ensure it is always topped up.

Get someone to drive behind you after the engine in your car has been running for 5 mins or so and check the exhaust gasses at different engine rpms and when accelerating and backing off. It could be blowing a small amount of blue smoke fairly constantly but you may not always see it looking back from the driver's seat.

If it was my car this is what I would do..........................

1. Have the PCV valve (crank case ventilator valve) checked to ensure it has not stuck in the open position.

2. Have a mechanic run a compression test on a couple of cylinders. If the compression is down significantly it is indicative of worn piston rings and oil will be gettiing past the rings and burning in the combustion chamber.

3. If 1 and 2 are OK then I suspect the most likely cause will be deteriorated valve stem seals which are allowing oil to find its way into the combustion chamber. Get someone to check your exhaust on start up after your car has been parked overnight. A blue smokey exhaust present on start up is indicative of worn VS seals. But you may also have worn piston rings if you continue to see some blue smoke so have the cylinder compression test carried out.