A year 2003 Wira 1.5 manual here. FC around 12.9-13.5km per liter with average speed of 130km/h. Is the FC ok? Anyway I got another problem, the fuel filter is always black colour when take out. Does any 1 here got this problem also? Thanks

When change that time can see is black. But the funny part is after the fuel filter blocked, I get better FC of 13.5-14km.

I can only say one word : pelik tapi benar.. Anyway got other members here encounter this problem?

Mine 3years 2months already done 100k...

Is it something like lagging?

Looks like is the intake valve after air filter blocked. Disconnect the air filter set(rubber parts) then open the valve manually and clean it using clean cloth. It should solve your problem. Anyway when you change your petrol filter, is it black or not?

Is it called throttle body? I think so, when the velve is open, the engine rpm will higher, like stepping on the accelerater. After clean it, you can see your car don't die on middle of idling.

Better to use semi rather than fully if the car is few years olf already.

Thanks for the info, know where to clean, but don't know the name..

As car's piston rings wear and tear over time, it is better to use mineral oil rather than semi or fully. I tried fully before on my 10 year old Iswara, it take 2 weeks to get my oil lost 50%

Injection cars cannot adjust timing by the screw, only can be done using a machine. The throttle body is when we step on the accelerater, the valve will open more.

Well, you cannot espect much on a second hand car, futuremore I do back-firing to clear the carbon on exhaust.

Unless you know that engine's piston ring have no big gap, then better to use semi first to check is there any oil lost when changing oil after 5kkm. Using semi, the lost will be around 5-10% if the rpm always maintained at 3-4k. If more than that, then is useless to use a fully, waste money only. A semi normal will cost around rm50-80 and fully around rm120-200.

If travel daily with milage more than 100km, Dunlop is the best choice if want to waste money, it can only last for 9 months.
If don't care much on noisy sound and want last long, Silverstone is the best choice. Even the Rainmaster cannot 'cut' water like Goodyear.
If want overall performance, Goodyear and Michelin is the best choice. For 14", price tagged at rm175 on my last change(March 2006). Now don't know the price already.