i have a b16a2 in my 95 honda civic and fuel pump will not prime. its a walbro 255lph fuel pump. all fuses are good and you can hear the relay click. before motor was installed when we would move the car the fuel pump did prime. any ideas? motor is fully built only thing holding us back. thank you
-brian

 

check your grounds: tranny, thermo, head.

 

bump

 

I would start by checking the voltage drop @ the positive & negative wires of the fuel pump.

 

Make sure your main relay is coming on as well and the fuse for the pump

 

You heard the main relay click, there are two relays inside, only one is for the fuel pump, you need to test further.

 

in for info, not thread jacking but just finished my shave/tuck/turbo install on my gsr turbo eg. Now my fuel pump isn't priming! checked all grounds, main relay clicks, checked all my fuses,but will double back on them.

 

You are going to have to see if power is going out of the main relay on the proper wire that goes to the fuel pump. If so, then check for power at the fuel pump. You can jumper the main relay just like any other relay.

 

its always something small and stupid with honda's......i ran a jumper from the main relay and was able to prime the fuel pump, checked the power leaving and coming to the main relay,fuel pump,all 3 grounds, under hood fuse box, coil on dizzy, injectors, map sensor, resistor box,and all had power! triple checked all my fuses, and rotated between 2 p28 ecu's! NOTHING!! new spark plugs, im just baffled!!

 

im goin to use a wire brush today and clean out the 2 grounds into the frame(because the bay was painted...maybe its not grounding properly...reason why fuel pump will not prime!)

 

You may have to gain access to the fuel pump harness connector and hotwire the pump.

 

Are you getting spark as well?

 

I'm getting a spark, and I have jumped my wire from the main relay and it shot fuel into my rail.

 

Pry open the two tabs on the main relay cover, remove the inner portion of the relay from the outer housing. break off the black covers from the two relays, be gentle. Plug the relay in where you can see it, maybe you will have to lay down upside down to see it under the dash with a flashlite. Turn the key on and see if you can see one or both relays working. If only one works, tap on the relay assy and the fuel pump relay may close for you. Either re-solder yours or get a new one, that is all it needs.

 

i just bought a new main relay 2 days ago from honda, so it can't be that.

 

Ok. You jumped the main relay and it worked, but replacing the relay, it doesnt work. The computer gives the ground for the main relay coil (your is not energizing) to close the fuel pump switch portion (you jumped the switch) of the main relay, so I am going to say, here on the internet, without testing your ECM, that your ECM is bad. Do you have a ground out by the thermostat housing with a few wires on it, clean all your computer grounds and try again.

For temp purposes, you can jump your relay to get around, but in an accident, this may be an issue so beware. You will need to remove the jumper when you are not using the car, it should not be a problem.

 

thanks for all the info, but i figured it out! it was my re-wiring of my new map sensor...there was an open wire that grounded it out. Everything works now.


-Mike