Well since it's been three months and you have not fixed it yet:
The owner must be broken!
Don't you love your baby? Fix it!
Change the timing belt, and the tensioner! Don't do it yourself. Get someone who knows what they're doing!
Check the fuel pressure!
Make sure there are no vacuum or intake leaks!
Check the exhaust backpressure! If the cats plugged you are running out of milage!
Look, I don't mean to be harsh, but you either have to take the leap and learn how to do the work - or take it to someone who already knows. The car won't fix itself. It will only get worse. So far as I have read, you have changed the plug wires and cleaned the injectors. Get serious about it.
Good luck !, but, get going!
