I have a 1992 Transport with 3.8L engine. I have not clean the injectors since new. The vehicle has 150,000 km What would be the best way to clean injectors? I don't care much about injector cleaner solution (add solution with a full tank of gas) such as STP from Canadian Tire or Walmart. I was told that I can not buy the same injector cleaning solution from garage so I must bring the vehicle in for service, is that true?
Quang