I found out that after changing the oil, and running about few hundred km's the oil smells like petrol and is dark brown in colour. I used liqui moly engine detox before the oil change and used penrite fully synthetic 10w40 oil. I also put in some wynns supreme engine treatment. Is it normal for the oil to be dark brown and smell like petrol ? The engine seems to run fine.

Is the car blowing any smoke at all?

I found out that after changing the oil, and running about few hundred km's the oil smells like petrol and is dark brown in colour. I used liqui moly engine detox before the oil change and used penrite fully synthetic 10w40 oil. I also put in some wynns supreme engine treatment. Is it normal for the oil to be dark brown and smell like petrol ? The engine seems to run fine.

The detox would have cleaned the engine and the oil is now showing the varnish that was loosened, hence the oil going dark quickly. The smell may be leftover detox or the engine treatment. Have a sniff at the empty bottles if you still have them. Probably the oil won't go much darker, but if it does, change it sooner than later.

Strange. I used the same detox and Wynns treatment, but used Castrol Edge Titanium 5w40 instead and after 3500km its still a nice caramel colour.
Is it the first time you've used an engine flush on this car? The darkness of the oil will likely be loosened carbon, sludge and varnish build-up

Hows the cars idling ? If one of the cylinders isnt firing, unburnt petrol can mix with the oil

This is the second time I'm using engine flush, I used it in the previous oil change, and the same thing happened, I changed the oil at around 7000kms. The car used to blow smoke when revved but now it does not seem to do so. When I removed the rocker cover, the cam was slightly bronze in colour, I think that's normal, but I don't know what the bottom end looks like.

If your engine runs rich it would cause the oil to smell like petrol.
Do you have poor economy and/or blow black smoke on throttle?

Does the car start OK? IF it doesn't then you may have an injector leaking when the engine is not running, and the petrol going into the sump. If it is fluffy when it does start, this is a likely cause.

I get around 16L/100KM city heavy traffic and around 8-10/100 highway driving. The engine runs smoothly and has good power, on start up there is some lifter noise despite the oil being new. Maybe it is normal for it to smell a bit like petrol?

Mine smells like petrol when you take the oil cap off.
But then again my car runs like crap half the time. Lol