Hello everyone,
I just bought a 91 TT with 85K miles. Car is super clean.
First thing I did was take it to my mechanic to freshen up the fluids.
However, after my mechanic did the oil change (20W40) the exhaust started to smoke a lot.
I took it back to him and he said he would try 20W50 royal purple. I live in South Florida so not sure if that helps.
Does this sound right? is using that heavy oil OK?
What are your thoughts?
Thanks!
Exhaust smoke after oil change
Re: Exhaust smoke after oil change
Sounds like hooey to me. Doubt it's related to the weight of the oil.
Re: Exhaust smoke after oil change
Last I checked 10w30 was the recommended weight for our cars... So that might be a good place to start.
Also what color/smell is the smoke and how is it coming out of the exhaust (clouds, wispy and etc...)
Also what color/smell is the smoke and how is it coming out of the exhaust (clouds, wispy and etc...)
Re: Exhaust smoke after oil change
there is a stupid idea that many mechanics have for some reason that makes them believe that worn piston rings demand higher viscosity oil. the idea is that if the oil is thicker it wont slip past the piston rings as easily therefor reducing the amount of oil getting into the combustion chamber. this is not how it works. it doesnt mean that your mechanic is an idiot, just that he's fallen for the meme like nearly all of them do. it's an ethnomethodological problem. 20w40 mineral is the standard workhorse diesel turbo oil grade. do your own oil change, use a group 3/4 turbo rated 5w30 synthetic oil and see if it helps. I say 5w30 because this is more standard for the group 3/4 oils that can withstand much higher temperatures.
this is a turbo vehicle with oil cooling lines to the turbos. you should never ever use a heavier oil in a turbo vehicle because it will kill your engine. its possible that changing the oil just cleaned up your passages, allowing oil to flow better through the engine, unblocking previously blocked oil lines and revealing a problem with your piston rings. you can check the piston rings by performing a compression check on each cylinder.
what color is the smoke? blue is oil, white is water, black is fuel. the blue smoke is white but it has a sort of blue color to it, you will know it when you see it.
this is a turbo vehicle with oil cooling lines to the turbos. you should never ever use a heavier oil in a turbo vehicle because it will kill your engine. its possible that changing the oil just cleaned up your passages, allowing oil to flow better through the engine, unblocking previously blocked oil lines and revealing a problem with your piston rings. you can check the piston rings by performing a compression check on each cylinder.
what color is the smoke? blue is oil, white is water, black is fuel. the blue smoke is white but it has a sort of blue color to it, you will know it when you see it.