Fuel pump relays location

2003 MITSUBISHI ECLIPSE
132,000 MILES • 3.0L • V6 • 2WD • MANUAL
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WTFADUCK
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I'm looking to find out where my fuel pump relays are at . Because drove it to work the after work it started then shut off. Then I started it back up the after a minute it slowly shut off then wouldn't start again. But I have read that i have got 2 fuel pump relays and need to know where there at.
Feb 28, 2020 at 8:51 AM
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STEVE W.
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The description sounds like a bad pump but it could be a lack of power to it. An easy check would be to spray some starting fluid into the intake and see if it runs, that confirms a lack of fuel. Both of the pump relays are in the junction box in the left end of the dash. They are in series and supply power to the green wire which powers the pump. Fuse 24 is the pump power feed, fuse 17 powers both relays. One relay should power on when you turn on the key and then stay on. The other turns on with a signal from the PCM so it won't click if you are turning on the key. Either one could cause the pump not to run as power has to go through both.
Feb 28, 2020 at 9:34 AM
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WTFADUCK
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Okay, I switched out the relays and changed the fuse. will my pump make a noise when I turn the key ?
Feb 28, 2020 at 4:53 PM
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STEVE W.
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It should run a prime cycle of about 2 seconds but you may not hear it. Some are very quiet. If it was a bad relay it should start with new parts. If it's the pump a spray of starting fluid should make it run a bit. The next thing would be to do a fuel pressure test. For that you need to disconnect the fuel line and attach an adapter to connect a gauge. You should see 45-50 psi if the pump works when you cycle the key and try to start the engine. If no pressure you would want to check for power at the pump. On your car it is an easy job. Remove the rear seat cushion. Under it you will find a cover that you can remove to access the pump. On it you will find the wiring. If you jumper battery power to the Green wire and the ground to the black wire the pump should run. If it does then you may have a wiring issue, likely a bad ground. If the pump doesn't run then replace the pump.

You might try the bang test, give the tank a couple good whacks with a rubber mallet or similar. Then see if the pump comes on and you can start the engine. If it does, replace the pump.
Feb 28, 2020 at 6:13 PM