Fuel pump or main relay?
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Fuel pump or main relay?
my car has a hard time starting when it's cold. i've already changed the battery with cap/rotor. still has the problem...
last night, my car didn't start; like usual when it's cold. when i put the key in (didn't start the car yet), i couldn't hear the fuel pump turn on. cranked it for awhile and the car wouldn't start. i have spark though. after about 15 minutes, i finally hear the fuel pump. crank it and the engine starts . now, would my problem be the fuel pump or the main relay. how can i check them? TIA.
last night, my car didn't start; like usual when it's cold. when i put the key in (didn't start the car yet), i couldn't hear the fuel pump turn on. cranked it for awhile and the car wouldn't start. i have spark though. after about 15 minutes, i finally hear the fuel pump. crank it and the engine starts . now, would my problem be the fuel pump or the main relay. how can i check them? TIA.
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Re: Fuel pump or main relay? (Ricey McRicerton)
if you can hear your fuel pump priming then i wouldn't think its your pump.
Modified by doublejz at 2:24 PM 3/2/2004
Modified by doublejz at 2:24 PM 3/2/2004
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Re: Fuel pump or main relay? (Ricey McRicerton)
i only hear the fuel pump after awhile. is the fuel pump known to be on/off when it's going bad like that? what about the main relay. help me out. i'm about to go buy a fuel pump from someone.
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Re: Fuel pump or main relay? (Unjockable)
just to make things clear, i only hear it priming after a long time of cranking it and sitting there. i don't the fuel pump every single time. on a side note, my car starts up fine in the morning (i park in a garage) and throughout the day.
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Re: Fuel pump or main relay? (Unjockable)
did a lot of search and came up with a few interesting things...
someone said "If you know you're getting fuel, it is NOT the main relay."
and most people say the main relay has problems when it's hot outside. i'm having problems when it's COLD outside. what's the deal?
someone said "If you know you're getting fuel, it is NOT the main relay."
and most people say the main relay has problems when it's hot outside. i'm having problems when it's COLD outside. what's the deal?
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Re: Fuel pump or main relay? (Unjockable)
That is correct that if you are getting fuel it's not the main relay. Since you are having an intermittent problem, I would think it's the main realy as they go in and out more than a dying fuel pump would. The main relay tells the fuel pump when to turn on.
#13
Re: Fuel pump or main relay? (Unjockable)
have you tried just turning the car on but not start it and see if the pump clicks on? When it's cold outside my car doesn't like to start unless I let the pump prime fully. So if you haven't already just turn the car to the on position, wait like 10 seconds, and then try starting it
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Re: Fuel pump or main relay? (FrostySol)
yes, the main relay clicks and the pump primes. but like i said, only after awhile of cranking it. only happens when it's cold.
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Re: Fuel pump or main relay? (Unjockable)
I'm having the same problem as you except in hot weather. I could tell you it is not the pump, because I replace it with the walboro 255 and I still have the same problem sometimes. I think it is the main relay but I'm not sure. It might also be the ignition switch.
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Re: Fuel pump or main relay? (Jun)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Jun »</TD></TR><TR><TD CLASS="quote">I'm having the same problem as you except in hot weather. I could tell you it is not the pump, because I replace it with the walboro 255 and I still have the same problem sometimes. I think it is the main relay but I'm not sure. It might also be the ignition switch.</TD></TR></TABLE>
i know it's not the pump because i just got one.
i know it's not the pump because i just got one.
#17
Re: Fuel pump or main relay? (Unjockable)
i think i have the same problem as you
symptom:
- drove sis to get her tire repair, when tried to start car the car wouldn't turn over and the fuel pump wouldn't prime. got a jump start but problem was gone when i got home.......weird.
- next day made a trip to home depot and when i got out to start the car, it died again. no turn over and no fuel pump. tried calling people but no one picking up so i chilled outside for 10 mins and tried to start car again......it started right away........when i got home problem was gone.
- i figured it might be the main relay because of the 10 min wait before i could start the car. also main relay cheaper then a ignitor/distributor/fuel pump so i went to honda and got one but didnt' install yet. wanted to check a few things to make sure it was definately the main relay before i rip the bag open.
- while looking at my spark plugs i notice something weird w/ my ground wire by val cover. it was rusted so bad the whole outter part of the wire looked like someone sheared it off and only the tiny middle part of the wire was holding it together.
check ignitor in distributor (swap it out w/ a friend to see if prob goes away), go get a main relay (40 online 50-60 at dealer) and check ground wires. good luck
http://honda.hybrids.jp/tech/p...shtml - main relay
symptom:
- drove sis to get her tire repair, when tried to start car the car wouldn't turn over and the fuel pump wouldn't prime. got a jump start but problem was gone when i got home.......weird.
- next day made a trip to home depot and when i got out to start the car, it died again. no turn over and no fuel pump. tried calling people but no one picking up so i chilled outside for 10 mins and tried to start car again......it started right away........when i got home problem was gone.
- i figured it might be the main relay because of the 10 min wait before i could start the car. also main relay cheaper then a ignitor/distributor/fuel pump so i went to honda and got one but didnt' install yet. wanted to check a few things to make sure it was definately the main relay before i rip the bag open.
- while looking at my spark plugs i notice something weird w/ my ground wire by val cover. it was rusted so bad the whole outter part of the wire looked like someone sheared it off and only the tiny middle part of the wire was holding it together.
check ignitor in distributor (swap it out w/ a friend to see if prob goes away), go get a main relay (40 online 50-60 at dealer) and check ground wires. good luck
http://honda.hybrids.jp/tech/p...shtml - main relay
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Re: Fuel pump or main relay? (slowturtle)
ok, just replaced the main relay and the problem is still there.
so far, i replaced:
battery
cap & rotor
fuel pump
main relay
any other things i should look at? has to be somthing that makes the fuel pump not prime when it's cold.
so far, i replaced:
battery
cap & rotor
fuel pump
main relay
any other things i should look at? has to be somthing that makes the fuel pump not prime when it's cold.
#20
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Re: Fuel pump or main relay? (Unjockable)
Instead of buying parts, buy a Helms and meter....shotgunning is going to get real expensive real quick.
If you have a new main relay and new fuel pump, you really don't have much else but the ECU, ignition switch and the wiring itself.
If you have a new main relay and new fuel pump, you really don't have much else but the ECU, ignition switch and the wiring itself.
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Re: Fuel pump or main relay? (93CivicSI)
are you stupid? you're telling me my brand new main relay is fucked up?
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 93CivicSI »</TD></TR><TR><TD CLASS="quote">Main Relay.</TD></TR></TABLE>
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 93CivicSI »</TD></TR><TR><TD CLASS="quote">Main Relay.</TD></TR></TABLE>
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Re: Fuel pump or main relay? (Unjockable)
This may sound stupid, but have you checked the ground for the Fuel pump? I know when I was swapping race seat in and out I knocked the ground loose and began having intermittent starts and fuel pump problems. After using a Helms and trouble shooting and coming up with nothing, I discoverd it was just a loose ground right next to the seat side bolster.
#24
Re: Fuel pump or main relay? (Unjockable)
I had a similar problem when I swapped. I went through some troubleshooting steps in my FSM and figured out it was a ground. My fuel pump grounds through the engine harness at the thermostat.
...Turned out that the bolt (that attaches the ground) had a couple of stripped threads. So it felt snug, but was nowhere near tightened down. I cleaned the contact surfaces w/ some sandpaper and threw in a new bolt. Problem solved.
The temperature issues might also point to that ground.
It's a longshot, but checking it is free.
GL
...Turned out that the bolt (that attaches the ground) had a couple of stripped threads. So it felt snug, but was nowhere near tightened down. I cleaned the contact surfaces w/ some sandpaper and threw in a new bolt. Problem solved.
The temperature issues might also point to that ground.
It's a longshot, but checking it is free.
GL
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Re: Fuel pump or main relay? (OBD1Kenobe)
just checked the ground and it seems fine. no corosion or anything. fits tight too. anything else i should check? i has to do with something that makes the fuel pump not turn on when it's cold.