City idsi mileage issue

[asimzaeem]

AOA Brothers
I have city 2007 manual 130K driven. Recently I have seen drop in its fuel efficiency. Car is now giving me 11.km/litre in city whereas 3-4 months it was giving me 13-14K in city (withou AC)

following work has been done 5 months ago
spark plugs changed / tappet setting/throttle clean
Engine is in good condition ( no smoke issue)
oil and filters changed regularly

Could you please guide what could be the reason?
for me 11Km is not what I expect from my car. People are getting around 15 on these cars
One downside could be that I m having R15 tyres instead of stock size but still I believe 11 km is way too low.
I drive it with light foot under 3000 rpm and drive it around 60km speed even then?

Can you suggest how can I get to 13-14km?

[babaralinawab]

milage after replacing spark plugs
If 20000 done and using standard spark plugs change them
If 2006+ model it also has a cat con have it cleaned
What oil are you using ?
Use 5w30 oil

[asimzaeem]

thanks for responding but let me add that

I have changed spark plugs 4 months ago and car only drove for 4K during this time
I used ngk spark plugs
as far as cat is concerned it had been removed because it was broken
using shell oil 10W 40
I m confused why mileage is going down
should I get it tuned up again?

[pwuser154420855868]

Cat Con , if removed, also results in low fuel average. The stock tyre is R13 , if I’m not wrong. The tyre size could be an issue as the size is quite larger than the stock size.

[asimzaeem]

cat is not totally removed but its inner jaali was broken so practically it was not functional
however it is still attached with silencer

[babaralinawab]

have injectors and 02 sensors cleaned then

[harishaf]

this is reason for low average.. get a perfect condition CAT installed and then avg will be better