To my experience with Toyota cars... is has been known to mankind that a Toyota car/truck with non OEM (NGK/ND) plugs would have problems... the NGK/ND plugs is the best plug you can get for your MK2... I have seen far better improvement in changing to the double platinum NGK/ND plugs and for the price... it is a little pricy... but with the discount at TOYOTA dealer... I could get them for 5 bucks a piece instead of 8-10 regular price. and it would last longer than the regular aftermarket subtitute... as what they have said 60,000 miles