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fuel pump relay?

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fuel pump relay?
« on: June 25, 2009, 06:36:00 PM »
hi all. 92 geo tracker was running fine. came home and next morning only cranked. a clicking or humming type noise comming from fuel pump relay. listened in tank and didnt hear pump. jumped relay wires and heard pump figured that was it. replaced relay and still same thing BUT the pump is on. also samr type noise under hood at egr  thing with 2 wires (blue base next to brown base by timeing cover)cant pull codes because check engine/service engine light doesnt work for some reason. any ideas? this is throttle body injected with a manuel trans. thanks all in advance.

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Offline Rhinoman

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Re: fuel pump relay?
« Reply #1 on: June 26, 2009, 02:54:26 PM »
99% probability that the ECU is shot, the relay clicking is the ECU constantly resetting to try and clear a hardware fault. The usual problem is that the electrolytic capacitors have died and the leaking electrolyte has eaten the power track away. Its not too difficult to repair, a TV/radio repair shop should be able to do the job at a reasonable cost. An ECU specialist will charge you for the 'knowledge'.
2000 Vitara 1.6, 3+3 Lift, 33"MTs, 5:83s, LWB brakes, Winch, Snorkel, Safari Rack
1986 SJ413K PickUp, 1.6L conversion.

OBD1 - Full diagnostics on a PC/Laptop: http://www.rhinopower.org

Re: fuel pump relay?
« Reply #2 on: June 27, 2009, 05:23:08 PM »
thanks for the reply. i was thinking computer too but the fuel pump relay was bad and also the fuel injector was bad. could the ecm have caused both to go at same time? it will run on starting fluid and i actually had it running twice on its own not great but running great at idle. but turn it off and no restart. its getting gas to throttle body and power to fuel injector but when you crank power goes away at injector. i pulled ecu out took apart and looked inside and saw nothing that looked bad,burnt or broken and also nothing smelled burnt either. tried grounding unit and still the same clicking sounds so i never even bothered to try it. has over 200,000 miles on it and the unit i pulled was from a junk yard so it was replaced b4 i bought it 10 yrs ago. any ideas or still sure its the ecu?

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Offline Rhinoman

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Re: fuel pump relay?
« Reply #3 on: June 28, 2009, 05:24:19 AM »
I've had a few ECUs that looked perfect but when the cap was removed the track underneath was all etched away. Its worth checking that the connectors on the ECU aren't dirty and tracing the earth wires back to the bulkhead. Where is the clicking noise coming from now? the fuel pump relay power is routed through the main relay so if the pump is on neither should be clicking. 
2000 Vitara 1.6, 3+3 Lift, 33"MTs, 5:83s, LWB brakes, Winch, Snorkel, Safari Rack
1986 SJ413K PickUp, 1.6L conversion.

OBD1 - Full diagnostics on a PC/Laptop: http://www.rhinopower.org

Re: fuel pump relay?
« Reply #4 on: June 28, 2009, 06:19:05 AM »
the clicking noise is still at fuel pump relay,the vss ( i think its called,the blue end next to the vss brown one) and on the throttle body at the isc solenoid i think its called.if i unplug the isc no fuel comes thru. i unplug the fuel pump relay and of course the pump doesnt work.if i jump the fuel pump relay pump comes on .if i unplug the vss thing it doesnt change anything. i cleaned coputer connections and re tried but nothing changed.you say  " main relay" where is that ? what does it do?  thanks

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Offline Rhinoman

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Re: fuel pump relay?
« Reply #5 on: June 28, 2009, 10:50:50 AM »
The main relay is usually next to the fuel pump relay and powers up all of the ECU circuits that don't have standby power. With an ECU failure you would expect both relays to be clicking.
2000 Vitara 1.6, 3+3 Lift, 33"MTs, 5:83s, LWB brakes, Winch, Snorkel, Safari Rack
1986 SJ413K PickUp, 1.6L conversion.

OBD1 - Full diagnostics on a PC/Laptop: http://www.rhinopower.org

Re: fuel pump relay?
« Reply #6 on: June 28, 2009, 02:18:18 PM »
my fuel pump relay is a stand alone relay nothing beside it. up higher by the ecu there are two more relays side by side. dont know what they are for? checked evrything again the tps is good, injector is good and i have an iac not an isc and that is good also. the other thing clicking is for the egr and thats blue and called a vsv not vss as i stated earlier. if i unplug the iac all clicking noisees  stop. unplug relay and only the relay stops. unplug the vsv and only the vsv stops. with the iac unplugged i have power to both injector wires with key on. plug it in and i get no power to injector. cranking or just key on no power. i plugged it in and ran jumper wires to injector wires while leaving it plugged in to activate tps and it still wont start. it is getting gas up to the throttle body. thanks for all the input and help.

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Offline Rhinoman

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Re: fuel pump relay?
« Reply #7 on: June 29, 2009, 04:14:14 AM »
If you run power wires to both sides of the injector you will burn out the injector, it must be pulsed.  You should read around 1Ohm across the injector. You can try running a power feed to the positive side, the ECU switches on the negative side. Have you measured the resistance of the ISC coil?
2000 Vitara 1.6, 3+3 Lift, 33"MTs, 5:83s, LWB brakes, Winch, Snorkel, Safari Rack
1986 SJ413K PickUp, 1.6L conversion.

OBD1 - Full diagnostics on a PC/Laptop: http://www.rhinopower.org