ea82blues Posted July 2, 2008 Share Posted July 2, 2008 My 94 Loyale lost a little power started up and ran rough then will not start. I pour a little gas down TBI (full tank) after checking fuses and it fires up. I got it home and read it has a relay to check. It does not. I traced wires from pump to a plug board where about 4 plugs connect together under pass dash. Parts stores do not list a fuel pump relay for a 94 1.8 tbi and there is no power @ pump key on. What controls my fuel pump because it is not working! bh Link to comment Share on other sites More sharing options...
zukiru Posted July 2, 2008 Share Posted July 2, 2008 you checked for power? or for a running pump? sounds like you did check for power but wasn't certain. get a test light to the run of wires and find out where the power stops (at least that's what i'd do.) also just because a parts store lists no relay doesn't mean there isn't one.. maybe you haven't found it yet. Link to comment Share on other sites More sharing options...
hooziewhatsit Posted July 2, 2008 Share Posted July 2, 2008 Try this: Under the hood, connect the two single-pole green connectors. Turn the key to 'on' - don't start it. The fuel pump should cycle on-off every second. If it doesn't, tap the pump lightly. If it starts cycling, you need a new pump. You can also check for voltage at the pump plug at this point. If you don't have voltage, you'll have to trace it back to the relay/controller. -Dave Link to comment Share on other sites More sharing options...
ea82blues Posted July 3, 2008 Author Share Posted July 3, 2008 I did trace wires they do not go to a relay they go to a plug. Does the spfi control unit on this last year of ea82 Loyales run the fuel pump? I will check with the dealer as his techs are off @ 3:00. I am aware of the green test plugs and this is my next step. I did a very close trace of these wires though and it is not where Haynes said it would be... Link to comment Share on other sites More sharing options...
ea82blues Posted July 3, 2008 Author Share Posted July 3, 2008 Where is the fuel pump relay on the 90-94 loyals with fuel injection? This is a 94 tbi 1.8L ea82 thanks Link to comment Share on other sites More sharing options...
dhise Posted July 3, 2008 Share Posted July 3, 2008 I had a fuel pump relay go out on mine in February of all months... Problem was that someone had replaced it with a generic relay and I couldn't find the color wires I was looking for right away. Anyhow, got a new relay, straightened out the wiring mess from the previous repair and it's good to go. For the winter months I bypassed the relay entirely and the pump ran whenever the key was turned on. Not entirely safe, but it was way too cold to be messing around at the time... I am pretty sure that all the loyales with the automatic seat belts have a seperate control unit that switches the ground for the relay instead of the ecu controlling it. -Doug Link to comment Share on other sites More sharing options...
ea82blues Posted July 3, 2008 Author Share Posted July 3, 2008 That is good news. I have been searching site and found a vauge post from MILES bout the relay being under the driver side dash behind the ECU. I assume thats the big silver Hitachi unit with three studs bolting it on. I have traced the wires to a plug board on passenger side. The plug the pump wires go into are routed to a bundle which go to driver side. Bad thing is I can not tell new color wires from the other side of plug that the blue and grey encased white fuel pump wires go to. I just know all wires are routed to the driver side. I dropped the ECU and there were two relays, one brown one blue just like MILES post. I got 12v reading on the brown plug and pulled the fuel pump fuse to no effect. The blue relay was supposed to be ignition so I got 12v on it and pulled ign/fuel fuse and it dropped to 0v. My Haynes book shows the fuel pump fuse to be the first one I pulled. It is labled fuelpump on fuse panel. MILES posted the brown relay as the fuel pump controler. The Haynes manual wire diagram shows no plug between relay and fuse so no help at all. Where is the dang thing for sure and how do you test it? I just love Subarus realy I do but Haynes might work for rebuilding a front end but this is starting to be weird. BTW I powered up the fuel pump with a M/C battery and started her up and revved to 4000 rpm... Thanks for the help but I am still unsure where relay is and how to test it! Link to comment Share on other sites More sharing options...
McDave Posted July 3, 2008 Share Posted July 3, 2008 I found this photo on GeneralDisorder's SPFI website. It's the blue one... http://home.comcast.net/~trilinear/EA81_SPFI/ECU_plugs_and_relays.jpg Link to comment Share on other sites More sharing options...
MilesFox Posted July 4, 2008 Share Posted July 4, 2008 the fuel pump relay will be hot on one side and it grounds thru the ecu. the ecu has to be live to ground out the relay to kick on the fuel pump. does the horn and clock work? they are on the 'hot all the time' circuit. check fuse number 5 "horn/clock/hazard fuse, since this also supplys 12v constant to the ecu. a common problem for this fuse going bad is during stereo installs when you would accidentally ground out the constant 12v green wire if you backfed 12v thru the green wire on the radio this should make the eu come live, if it is in fact dead good luck Link to comment Share on other sites More sharing options...
MilesFox Posted July 4, 2008 Share Posted July 4, 2008 Link to comment Share on other sites More sharing options...
ea82blues Posted July 6, 2008 Author Share Posted July 6, 2008 This is the trouble shoot for fuel pump. The first ? is do you listen to relay to see if its working like in test mode? To access the relay you have to unbolt control unit. Will the relay work if ECU control unit is not grounded (installed)? To further trouble shoot you need to test control unit blade l/b. I assume you unplug the relay connector and checkfor voltage? It seems the ecu should be installed (grounded) to do this. The final test is similer but checking for resistance and I have the same ?'s about the test Link to comment Share on other sites More sharing options...
ea82blues Posted July 6, 2008 Author Share Posted July 6, 2008 sorry for the huge image... any thoughts experience with this trouble shoot so I don't screw it up? Thank You all Link to comment Share on other sites More sharing options...
Gloyale Posted July 6, 2008 Share Posted July 6, 2008 sorry for the huge image... any thoughts experience with this trouble shoot so I don't screw it up? Thank You all The ECU is grounded by several wires, not it's mounting. no worries leaving it hang during testing. For testing voltage at the relay, leave the connector plugged into the relay, and probe from the back side of the connector. (in fact that is ALWAYS how Fuji says to test them, diagrahms are always shown looking the back of the connector) BTW, any time you see an *L* labeled wire, that means *blue*. *B* means black. If it is *L/b*, that means *BLue w/Black stripe* Link to comment Share on other sites More sharing options...
Cougar Posted July 6, 2008 Share Posted July 6, 2008 I think the relay is up above the fuse panel area or above the steering column possibly. The problem may be with the relay or possibly the control unit. You may be swap the relay with another one in the car once you find it. Link to comment Share on other sites More sharing options...
Reveeen Posted July 6, 2008 Share Posted July 6, 2008 In an emergency you can steal 12V from your rear lights, butchering something up under the rear seat, of course you will have to drive with your lights on, but it will get you home. Link to comment Share on other sites More sharing options...
ea82blues Posted July 6, 2008 Author Share Posted July 6, 2008 The ECU is grounded by several wires, not it's mounting. no worries leaving it hang during testing. For testing voltage at the relay, leave the connector plugged into the relay, and probe from the back side of the connector. (in fact that is ALWAYS how Fuji says to test them, diagrahms are always shown looking the back of the connector) BTW, any time you see an *L* labeled wire, that means *blue*. *B* means black. If it is *L/b*, that means *BLue w/Black stripe* Perfect:clap: Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now