@naweed: the thing you mentioned regarding the rust on spark plugs which could be a result of improper combustion and knocking, does it mean that the fuel injectors may be clogged? How can this improper combustion be improved? and about the spark plugs i have done some research and you are right the recommended is 1.1 mm, even i am amazed what did he mean by 14 or 22.
@capsat: i am avoiding any use of off-the shelf cleaning agents, plus I am also avoiding from any improper person to handle the fuel injectors, but I am disappointed that toyota does not provide any service of fuel injectors. after getting the oil change i will go for a compression test after driving a few kilometers.....
but one thing that worried me was that I got this work done yesterday, then in the evening I traveled from pindi(DHA) to islamabad (I-10), there was some knocking right in the beginning, but it knocking completely died after about 5-6 Kilometers...and the car drove smoothly....but on my way back (Isl-pindi), there was heavy knocking in the engine and i just could not drive the car smoothly, although it might have been due to a bad fuel factor but the knocking really bugged me.
Thank you for all the suggestions, i will keep you posted about the condition.....and keep getting suggestions from you guys
I will definitely get in touch with storm/spectra for RWP/ISL region