Fuel pump relays can cause intermittent problems such as hard starting and power loss. The first check is to listen each time you turn the ignition key, you should always hear the electric fuel pump run (a whirling noise) for a few seconds as the pump pressurizes the fuel system. After the fuel pump pressurizes the system, it shuts off. If sometimes you do not hear it and have a hard or no start problem check the fuel pump relay as described below.
See what pin type you have. Generally 4 or 5 pins.
If four pins, remove relay and bench test as follows:
Using an ohm meter, check between pins 85 and 86. If reading is more or less than 85 ohms replace the unit.
If five pin type, remove relay and bench test as follows:
Using an ohm meter, check between pins 85 and 86. If reading is more than 120 or less than 40 ohms replace the unit. Check between pins 85 and pins 30 and 87, if less than 10,000 ohms replace the unit.
If the relay shows burning or distortion from heat, replace the unit and check the plug for damage. If the relay checks good, proceed to a fuel pressure and volume test.
These relays are not expense and are handy for many applications as they have a good amp rating.
