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Little bit of blue smoke when giving gas after idling for a while

11000km in and my E46 316i has been fun and also a bit of pain but now the engine just feels different to me.
When I open the hood and it’s idling it just doesn’t sound like it used to and I think it vibrates some more then normal. When I leave it idling a bit or when I do a cold start it puffs out some blue smoke but after a few revs it’s all gone no more smoke whatsoever. I have no more oil leaks (changed every gasket and do check ups every week.) and the engine still runs fine but it just doesn’t feel the same and it’s pretty concerning. Can’t be the head gasket since I don’t notice oil in that area and my coolant is on perfect level and the car temperature is always optimal. Anyone might have an idea what it is ?

To me it sounds like oil, possibly through the valve guides. But at 11,000 km isn’t it still under warranty?

It’s an E46 as mentioned so it’s an old car (16 years) but since I’ve had it I did 11k with it

That is why we ask for Make, year, mileage, and engine.
If I said E Class with 45,000 miles, would you know I was talking about an 83 Chrysler?

When it comes to head gaskets, cars are fickle. They might not give you typical head gasket symptoms. My car was one of those. It didn’t overheat, it just ran slightly warmer than usual. I had to waive diagnostic warranty to get a shop to do my head gasket, because nobody would say I needed one if my car didn’t give the typical head gasket symptoms. It turns out, based on what my mechanic found, I needed a head gasket after all.

So don’t rule anything out based on a lack of symptoms; that’s a logical error.

E46 what ? I did not know Hupmobile made a model E46.

Don’t care how many miles you have driven this thing, how many miles does the vehicle have on it ? Is it gas or diesel or even electric. ? It would also help if you said what country you are in.

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It’s a BMW 316i, E46 (fourth) generation of the 3 series. It has a gas 4 cylinder engine. I don’t think this model was sold in the US.

BMW E46 316i LCI 2003 170639km N42B18A

How much oil does it consume? Given the mileage, could easily be valve guides, rings, or even a gummed up crankcase evap system. PCV, vapor trap, egr valve ect.

My guess is a problem w/the valve guide seals. Usually this would be accompanied by a little more than normal oil usage, but not a lot more (maybe one quart per 750-1500 miles), possibly some oily residue inside the end of the tailpipe, and some visible signs of oil getting onto the tips of the spark plugs. On many engine designs it is possible to replace those w/out removing the engine from the car, or the head from the engine.