Excessive fuel consumption in the city

To much consumption of fuel

What kind of oil can I use for my kia Rio
Mileage 180k

I replaced spark plugs, PVC valve, air engine filter, throttle body cleaned, but is still eating a lot fuel

Purchased this 2013 kia rio hatchback 2 months ago. I was drawn to this vehicle because of it's decent fuel economy. I've put roughly 550 miles on this car since my purchase. From day one the onboard computer was showing around 12mph average. My personal ledger shows the same around 12mpg average. Can anyone help me here? I cannot seem to find any info on what is the problem.

Oil light, noisy engine, high fuel consumption

The car fuel consumption is high, it was in a flood , a few years ago. Whilst driving, the car will just surge, like a power dip. If I lift my foot slightly, it loses power. No codes, no fault codes. All sensors are new, filters are new. Up hill I have to accelerate higher, the eco green goes out easily. The things I didnt check yet, is the CAT and gear box( automatic). Your advice will be appreciated.

Seems to start fine initially and drive fine as well. Recently at very random occasions (like if I stop for gas) it seems as though my Kia won’t start. The lights come on, it makes the sound as if it’s cranking but nothing and then all the lights go completely off or dim. This has happen three times as of today over then span of two months and two of the times it has reset my dash view. (Trips starts back at zero or changes from viewing mileage left in tank to a trip or avgerage gas mileage. ) there doesn’t seem to be any warming as to when it happens and there has not been any signals lighting up in the dash and the car gets regularly serviced it just happens. Any thoughts?