Fuel Injectors
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The fuel injector is a solenoid-operated valve that meters fuel flow to the engine. See Fig 1. The fuel injector is opened and closed a constant number of times per crankshaft revolution. The amount of fuel is controlled by the length of time the fuel injector is held open.
The fuel injector is normally closed and is operated by 12 volt VPWR from the electronic engine control power relay. The ground signal is controlled by the PCM.
CAUTION:
DO NOT apply battery positive voltage (B+) directly to the fuel injector electrical connector terminals. The solenoids may be damaged internally in a matter of seconds.
The injector is the Deposit Resistant Injection (DRI) type and does not have to be cleaned. However, it can be flow checked and, if found outside of specification, the fuel injector should be replaced.