Removing a fuel injector without removing the plenum isn’t without risk. Grinding of the upper plenum will be involved with the possibility of completely grinding through the plenum wall thus ruining the plenum. The trade off is several hours of labor and many dollars saved by not having to replacing a slew of gaskets and hoses.
*8mm Ball end Hex wrench (Allen wrench)
*Dremel rotary tool w/assorted grinding bits
*Voltmeter w/Ohm measurement
*Assortment of Phillips screwdrivers
Once a malfunctioning fuel injector is detected, rather through a CEL or common sense, the first step is to identify which injector has failed. There are two ways to identify the faulty injector.
1) Using a mechanics stethoscope place the scope on each injector until you find the one not ‘clicking’ while the engine is running. Voila, 60 seconds later you know which injector is dead. This is definitely the easiest and quickest method.
2) The 2nd method is done by measuring the resistance of each injector. I recommend double-checking the assumed failed injector with this method to verify it needs replacement and it’s not the coil pack that has failed. The factory specification of the injector is 10-14 Ohms. If the reading exceeds this range then replacement is necessary. This is how the measurement was made:
Checking Fuel Injector
1) Remove the throttle cable cover. This will require the 8mm Ball end hex wrench. There are 5 screws to remove.
2) Although not all can be seen but I’ve circled the approximate locations of the FI’s.
3) Now remove the wiring harness from each FI (if not using the stethoscope method) or just the single harness (if the stethoscope method was used). The harness can be a little tricky to get off. While doing this you should check for corrosion on the connections, as this could be a cause of the malfunction. In some instances, depending on the cylinder, it may be beneficial to disconnect the coil pack and move the wiring and harness out of the way.
4) Once the FI harness is removed use your voltmeter to measure the resistance of the FI. Use the two prongs surrounded by the red plastic to take your measurement. If it is good and in spec it should measure 10-14 Ohms. If it is out of this range it needs to be replaced.