The definition of a rule is  an official regulation, code of regulations or set practice. An example of a rule is that a red light means stop. An example of a rule is an employer demanding their employees arrive at 8am.
New injectors cost anywhere from $80-$120 apiece, making their replacement a somewhat pricey endeavor. There are three types of injector leaks-it can leak fuel into the manifold from the nozzle, it can leak fuel into the engine compartment from the fuel rail, and it can leak air (vacuum leak) from the manifold.
How much does fuel injector cleaning cost? On average, a fuel injector cleaning will depend on the âlevelâ of cleaning that is required. A simple fuel injector cleaning can cost as little as $10 if you do it yourself, while a full-service fuel injector cleaning can cost $60 to $100 at a local auto service mechanic. For instance, PepBoys.com offers three packages that range from $9 to $90.