I am using a Maruti 800.I have replaced the all drive belts(including timing belt)at odometer hits 50000km(sparking plugs also replaced at this time). Now odo reads 51000km.Once I was driving it I noticed its bit lazier in acceleration and stucked in a steep slope.(I was using M800 previously & it was not like this even odo at 89000km.Once I smoked a vitz(needless to say auto transmission )in a casual drag) is servicing it at Udawat*a Motors at Maharagama & when she put it to regular maintenance there, asked about this. Then they have asked whether T belt is replaced and requested to do a tune up. Further they said while tuning up they use a special fuel so fuel circuit also will clean. Charge is 6500LKR. Furthermore this car is having a slightly large balloon size tires added by previous owner.Handling is not a problem as they rarely exceed 50kmph Will engine tune up will fix my problem?

Please help.

I didn't find the right solution from the Internet.

Maruti 800 Engine-Tune Up - General - AutoLanka
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