no power to fuel pump, got new main relay and checked the ground
09-14-2011, 05:55 PM
#1
no power to fuel pump, got new main relay and checked the ground
im trying to get the integra to start and no luck.
my wife had the main relay issue few months ago and cleaning the ground and new relay fixed it.
but this is a bit strange.
all the fuses have been checked many times
1 i checked the ground on thermostat it was good.
2 the main relay starts buzzing only after crank sequence.
meaning theres no sound from it untill after i turn the key to crank and let go.
it stops buzzing while in cranking.
fuel pump is not priming.
put new main relay on and its same thing.
i jumped the black wire to the ground and it will turn over but wont start and the wire gets warm so i disconnect it before it gets hot.i know its bad sign but i had to see it anything is alive at all.
when jumping the 2 yellow wires in main relay connector the fuel pump supposed to turn on but it didnt.
it is cranking with black wire grounded so i ruled out the alarm and fuel pump kill switch.
but dont know if theres another ground somewhere that i forgot or something.
my wife had the main relay issue few months ago and cleaning the ground and new relay fixed it.
but this is a bit strange.
all the fuses have been checked many times
1 i checked the ground on thermostat it was good.
2 the main relay starts buzzing only after crank sequence.
meaning theres no sound from it untill after i turn the key to crank and let go.
it stops buzzing while in cranking.
fuel pump is not priming.
put new main relay on and its same thing.
i jumped the black wire to the ground and it will turn over but wont start and the wire gets warm so i disconnect it before it gets hot.i know its bad sign but i had to see it anything is alive at all.
when jumping the 2 yellow wires in main relay connector the fuel pump supposed to turn on but it didnt.
it is cranking with black wire grounded so i ruled out the alarm and fuel pump kill switch.
but dont know if theres another ground somewhere that i forgot or something.
09-14-2011, 08:06 PM
#2
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Re: no power to fuel pump, got new main relay and checked the ground
did you put a meter on the power wire to the pump to really know that its getting power? You need to stop playing these touch wires together stuff and I hear clicking from a relay.
Check for voltage at the pump. Check that there is ground.
start there
Check for voltage at the pump. Check that there is ground.
start there
09-14-2011, 08:48 PM
#3
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Re: no power to fuel pump, got new main relay and checked the ground
I ran into this problem once before with a 5 speed car and it turned out to be the switch for sensing when the clutch pedal was engaged.Another one i had was an auto tranny because of the neutral safety switch.But this one had fuel pressure.
09-14-2011, 08:50 PM
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Re: no power to fuel pump, got new main relay and checked the ground
Oh yeah Like hybridmiklo is sayingyou need to forget about past issue start from the beginning without skipping any steps.K>I>S>S no offense but keep it simple stupid.
09-15-2011, 12:34 PM
#6
Re: no power to fuel pump, got new main relay and checked the ground
Read through this thread, might give you an idea on what to look for.
https://honda-tech.com/forums/acura-integra-6/fuel-pump-not-priming-solid-cel-2952478/
https://honda-tech.com/forums/acura-integra-6/fuel-pump-not-priming-solid-cel-2952478/
09-15-2011, 06:57 PM
#7
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Re: no power to fuel pump, got new main relay and checked the ground
Questions...
MM&Y of car?
When you say, "im trying to get the integra to start and no luck" does that mean engine cranks, [starter working] but will not fire, [start/run] or do you mean engine will not even crank, [starter not working]?
When you say, "i jumped the black wire to the ground and it will turn over but wont start" excactly what does that mean, what black wire and what gauge is the "jumper" wire?
A relay that is "buzzing" is an indication of a poor ground, [ground side of relay coil] poor power, [power side of relay coil] or a shorted output.
Drop relay so you can hold it in your hand while still pugged in, turn ign. swith on to run, [not start] you should feel/hear 2 "clicks' from the PGM-FI Main Relay, the first click is the injector relay turning on, the second click is the fuel pump relay turning on.
The clicks are very close together so it can sound/feel like one click, at that point, [after second click] the CEL should turn on and the fuel pump should prime, [run for a few sec.] then there will be a 3rd click, [fuel pump relay turning off] CELL will go out and pump will stop priming.
If the above is not happening, obviously there is a problem, so start by checking for the 3 powers to the PGM-FI Main Relay.
1- Unplug the relay and with the ign. switch off there should be one lead with power, most likely yellow/white [hot at all times].
2- Now turn ign. switch on to run, there should now be 2 leads with power, the first one, [hot at all times] and the 2nd one, most likely black/yellow or yellow/green, [hot in run and start].
3- Now turn ign. key to start, [if CIS is working or if you unplug the starter lead from the starter, engine will not crank, making this test easier] there should now be 3 leads with power the first one, [hot at all times] the 2nd one, [hot in run and sart] and now the 3rd one, most likely a blue/white, [hot only when cranking to start].
If you do not have the above 3 powers, [hot at all times, hot in run and start and hot only when starting] you will need to find the problem.
The first power, [hot at all times] is the power input to the fuel injector relay, [#30], the output from the fuel injector relay, [#87] powers, [goes to] the injectors, ECU/ECM, [IPG1&2] and a few engine solenoid/valves, it also goes to fuel pump relays coil, [#85] and is internal, [no leads outside of PGM-FI Main Relay].
The second power, [hot in run and start] powers, [goes to] the injector relays coil, [#85] the other side of injector relays coil, [#86] is the ground, [black lead] andit also goes to the fuel pump relays input, [#30] it is also internal.
The third power, [hot only when cranking to start] powers, [goes to] the fuel pump relays coil, [#85] it is paralleled, [internally] with the output power of the injector relays output, [#87], it is a "back-up" power for the fuel pump relays coil during cranking to start.
That will leave you with only three other leads on the PGM-FI Main Relay plug, the output from the injector relay, most likely yellow/black and the output from the fuel pump relay, most likely yellow/green and the ECU/ECM control lead for the fuel pump relay, most likely green/blue.
If the wire colors are as described above, 94-up Integra and you have all 3 powers try jumping power directly to fuel injectors and the fuel pump, ign. switch can be off, with relay unplugged jump from the yellow/white, [hot at all times] to the yellow/green, [fuel pump power lead] you should hear the fuel pump running, if not and/or if jumper gets hot, check fuel pump and/or fuel pump power lead between relay plug and fuel pump plug, [under back seat], if pump does not run it may be the pump or a connection problem, if jumper gets hot there is a short in the fuel pump power lead or the pump itself, a sort in either one would cause relay to "buzz".
Do the same with the fuel injector lead, [yellow/white to yellow/black], the same goes with it, if jumper gets hot you have a short and it would cause injector relay to "buzz", you will have to test the power leads at the injectors, [to see if power is getting to them, your will also have to test IPG1&2 on the ECU/ECM to see if there is power to them and at the engine solenoid valves, [IABCV, EEPCV, IACV and heated O2 sensor].
If your an eyeball kind of guy, you can slide the cover off the PGM-FI Main Relay so you can see what is happening, [what relays do, which one buzzes]is turned on to run and start.
Feel free to IM me if you have questions.94
MM&Y of car?
When you say, "im trying to get the integra to start and no luck" does that mean engine cranks, [starter working] but will not fire, [start/run] or do you mean engine will not even crank, [starter not working]?
When you say, "i jumped the black wire to the ground and it will turn over but wont start" excactly what does that mean, what black wire and what gauge is the "jumper" wire?
A relay that is "buzzing" is an indication of a poor ground, [ground side of relay coil] poor power, [power side of relay coil] or a shorted output.
Drop relay so you can hold it in your hand while still pugged in, turn ign. swith on to run, [not start] you should feel/hear 2 "clicks' from the PGM-FI Main Relay, the first click is the injector relay turning on, the second click is the fuel pump relay turning on.
The clicks are very close together so it can sound/feel like one click, at that point, [after second click] the CEL should turn on and the fuel pump should prime, [run for a few sec.] then there will be a 3rd click, [fuel pump relay turning off] CELL will go out and pump will stop priming.
If the above is not happening, obviously there is a problem, so start by checking for the 3 powers to the PGM-FI Main Relay.
1- Unplug the relay and with the ign. switch off there should be one lead with power, most likely yellow/white [hot at all times].
2- Now turn ign. switch on to run, there should now be 2 leads with power, the first one, [hot at all times] and the 2nd one, most likely black/yellow or yellow/green, [hot in run and start].
3- Now turn ign. key to start, [if CIS is working or if you unplug the starter lead from the starter, engine will not crank, making this test easier] there should now be 3 leads with power the first one, [hot at all times] the 2nd one, [hot in run and sart] and now the 3rd one, most likely a blue/white, [hot only when cranking to start].
If you do not have the above 3 powers, [hot at all times, hot in run and start and hot only when starting] you will need to find the problem.
The first power, [hot at all times] is the power input to the fuel injector relay, [#30], the output from the fuel injector relay, [#87] powers, [goes to] the injectors, ECU/ECM, [IPG1&2] and a few engine solenoid/valves, it also goes to fuel pump relays coil, [#85] and is internal, [no leads outside of PGM-FI Main Relay].
The second power, [hot in run and start] powers, [goes to] the injector relays coil, [#85] the other side of injector relays coil, [#86] is the ground, [black lead] andit also goes to the fuel pump relays input, [#30] it is also internal.
The third power, [hot only when cranking to start] powers, [goes to] the fuel pump relays coil, [#85] it is paralleled, [internally] with the output power of the injector relays output, [#87], it is a "back-up" power for the fuel pump relays coil during cranking to start.
That will leave you with only three other leads on the PGM-FI Main Relay plug, the output from the injector relay, most likely yellow/black and the output from the fuel pump relay, most likely yellow/green and the ECU/ECM control lead for the fuel pump relay, most likely green/blue.
If the wire colors are as described above, 94-up Integra and you have all 3 powers try jumping power directly to fuel injectors and the fuel pump, ign. switch can be off, with relay unplugged jump from the yellow/white, [hot at all times] to the yellow/green, [fuel pump power lead] you should hear the fuel pump running, if not and/or if jumper gets hot, check fuel pump and/or fuel pump power lead between relay plug and fuel pump plug, [under back seat], if pump does not run it may be the pump or a connection problem, if jumper gets hot there is a short in the fuel pump power lead or the pump itself, a sort in either one would cause relay to "buzz".
Do the same with the fuel injector lead, [yellow/white to yellow/black], the same goes with it, if jumper gets hot you have a short and it would cause injector relay to "buzz", you will have to test the power leads at the injectors, [to see if power is getting to them, your will also have to test IPG1&2 on the ECU/ECM to see if there is power to them and at the engine solenoid valves, [IABCV, EEPCV, IACV and heated O2 sensor].
If your an eyeball kind of guy, you can slide the cover off the PGM-FI Main Relay so you can see what is happening, [what relays do, which one buzzes]is turned on to run and start.
Feel free to IM me if you have questions.94
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