legacycentral bbs

So when you turn key on, you should get 12 colts for a second to prime fuel system. Then the voltage drops to 3.5ish and sits there till car is started and the voltage is turned back on to 12.

Mine has decided to not do the 12 part and just sits at 3.5. The relay is clicking when key is turned off and on.

What am i missing?

Currently just hotwired the pump.

Hi Doug,

Long time no talk. Hope you are good!

If you connect the green diagnostic connectors do you get 12v on and off when the relays engage or still the 3.5v?

If you're still only get the 3.5v then it could be the fuel pump relay or something in the wiring from the relay to the pump. Have you tried checking things with a multimeter and tracing down the wiring diagrams?

https://surrealmirage.com/subaru/files/ ... rical1.jpg

Relay is clicking.

Do you know what causes the 3.5 to 12 volt action?

Hot wire is working fine.

Sorry Doug....just seeing this post.

If with the green diagnostic connectors connected you're seeing voltage go from 12 to 3.5v then that would tell me that the relay is working and the ECU is working because it's telling the fuel pump relay to cycle. Check the voltage on the ECU's F47 connector, pin 23. With the ignition switch on (engine off) you should have 0.7V. With ignition switch off you should have 10-13V. With the engine running you should have 0.7V.

It appears that something is not allowing the ECU to turn on the fuel pump. I do know that the ECU will prime the pump on key on and then will only apply voltage to the fuel pump when it detects cranking. Are you getting any other codes? Does the engine run if you "hot wire" the fuel pump?

I checked "notify me when a reply is posted" so should be a little quicker with the reply

Does the engine run if you give it a good bunch of starting fluid down the intake?