it is very difficult to guess what your problem as it could cost a lot of money just by guessing what it is.I can only advise as to what other motors with similar problems were,if it is reaching a maximum of 60km/hr and getting no more power then the air flow meter may be worth a look,also the crank sensor and make sure your filters are clean incliding your fuel in line filter.It may be worth visiting a scrappy for 2nd hand parts to save you cash as there are no guarantees your fault will be cured.
cdc, April 2013