'89 240SX Fuel Pump Won't Shut Off

[SeVa-S13]

I have an RB20 in my 240SX and something is amiss with the wiring somewhere. I have the top of the relay off and 2 of the connections jumpered to get the fuel pump to turn on. I need to know how to ghetto rig/hardwire the fuel pup relay to get the fuel pump to shut off. AT the "ON" position, it will pump continuously when it's supposed to stop after a second after it's filled the lnes and fuel rail. I have a HiFlow Walbro fuel pump installed so it's pumping *alot* of fuel and at idle, the car will run so rich I have to rev it to keep it alive and the exhaust reaks of fuel, plus it makes my eyes water. Uncool.

For those unfamiliar with the relay, there are 4 connections arranged like this:1234

1 runs to the ECU. 2 runs to the Fuel Pump. 3 & 4 both run to a 10A fuse in the same fuse box as the relay in question.

The top of relays give a little diagram and it shows 1 being connected to 3 via a dual looping squiggly line. I'm guessing that's a ground?Connection 2 connects to 4 but has an arrow that breaks away from it.

I need to know what (ECU or fuel pump) device(s) to connect to which connections to get my fuel pump to function properly.

:help

[s13sr20chris]

thats funny. most nissan relays have 1 and 2 as the coil side and 3 and 4 as the switch side. ok squiggle is the coil. when current flows it heats up and draws the switch closed. the switch is the open arrow thing in the diagram. as you can see the numbers you give are not typical. anyway, dont ever use a jumper to connect the two wires that go to the coil side of the relay. if you jumped them then you just shot straight 12v to your ecm. the ecm attempts to ground straight 12v with no resistance(to speak of) in there anywhere and just burns up. you may possibly have burnt the ecm fuel pump circuit. you can wire it to the ign switch but it will not give you the 5 sec pulse at initial key on. check the ecm by checking for ground at the relay terminal that goes to the ecm. it should give you ground under the conditions of fuel pump operation and nothing under other conditions. in other words, key on will give ground for 5 secs and then provide constant ground with engine running.

[Hijacker]

i talked to him and found out he hadn't swapped the connector pins at the engine->chassis plug to connect the fuel pump up. it hasn't been recieving an ECU signal.

[s13sr20chris]

ok good!

[Hijacker]

well, getting the wires hooked up properly didn't fix the problem. My next guess is relay. He can take the wire running directly from the ECU and touch the top of the relay and get the pump to turn on, but it won't turn on when the wiring is done up. I remember a few weeks ago, he told me he was taking it for a test drive and then the pump stopped working in the middle of the test run.

All of that stacked up makes me think the relay is blown.

Also, the fuse is not blown

[SeVa-S13]

Well upon closer inspection of the realy, I don't think the bottom part (where the wires connect) of the rely can blow. All the business happens up top, doesn't it? I've tried multiple different relay tops to the same end. I called my dad and woke his *** up but he was able to lend some good advice which should come to final fruition tomorrow at which point we'll either be starting all over again or I'll have a driving car.

[s13sr20chris]

relay top? you mean the plug in part? as long as you have power and ground on two terminals each under the circumstances that the fuel pump should be operating with low voltage drop the relay would have to be bad. whack it with a screwdriver.

[euroboy]

ok i had the same problem with my 200sx s12 with ca18det in therefp wouldn't shut off. So i build a relay to shut it off after the key has been turned off. But this now made it not come on at all so i build another relay to run it on. SO my fp has 2 relays plus the main one. When you hook up to turn it on make sure you get a continous power not you turn key and s*** shuts off...find on the fuse box which one is contionous and take current from there and directly from the eu