krysted9354

ok, u know when u turn the ignition on the fuel pump will prime for 2 seconds and turn off,,


What contols that the ecu ??

as i replaced the fuel main relay,

is there a common problem with the ecu fuel part braking ?


as question is WHAT turns fuel main relay on,

the part that turns fuel pump on doesnt work, what controls that ,ecu ?

Former User

Yes, the ECU controls turning OFF the fuel pump after 2 seconds if it doesn't detect the engine turning (signal from distributor sensor).

What year Civic? Have you checked for blown fuses under the hood and dash? Is the ignition switch possibly bad?

krysted9354

ok so ecu turns fuel pump of after secinds right ? or some relay ?

Former User

The ECU provides ground to the circuit in the main relay that switches the fuel pump ON. If the engine is not turning, the ECU removes ground for the circuit after two seconds.

krysted9354

ok so if the ecu is not doing that whats broken ? when u turn key the fuel pump is not priming, and i replaced the relay and also banked it ?

Former User

What year Civic? Start by checking whether any of the main relay fuses are blown under the hood and dash.

Does the fuel pump run if you wire it directly to the battery?

Dose the engine have spark?

Is the critical ground wire attached to the thermostat housing clean and tight?

When you turn the key to ON(II), does the CEL remain ON or does it turn OFF after 2 seconds?

krysted9354

96

yes fuel pump turns on when i add ground to relay,

yes i have spark

no cel turns on at all ~


which wire form the ecu is it ? i will just take wire from there straight to the relay ?

Former User

Which wire did you ground to make the fuel pump run?

Do you have continuity on the Grn/Yel wire that runs between the main relay and ECU (A16)?

Are you saying the CEL light doesn't work -- never turns ON?

watisjdm

there is a green plug in passanger floor board near the ecu...see if that is still plugged in

krysted9354

no green plug is not plugged ? were it go ?


and the cel never turns on, but bulb is good and i checked it.

Former User

Are you talking about the 2P service connector or one of the ECU connectors? Clearly, if one of the ECU connectors isn't plugged in, then you likely have found the problem. This also might be the cause of no CEL.

If you instead happen to be looking at the service connector, then someone may have cut a wire to disable the CEL circuit. Here's how to troubleshoot:

krysted9354

and yes the g/y has power , i have apower on all 3 on the relay, i have power on 1,3,5 all 3 vof thoe on what the relay states numbered/

when i ground 8 everything is good. number 7 is to the fuel pump

krysted9354

i have aseent the cel turn on once before, but thats with the old enigne now i swapped in a d15z1 and just trying to start it c how ti runs.

Former User

What ECU are you using?

How many terminals does the loose connector have?

krysted9354

im using stock d16y7 ecu,

ecu has 3 plugs that go into it, and theres 1 green one hanging with oh 10+ wires in it, im guessing abs ?

watisjdm

its a green plug near the ecu plugs but its not an actually ecu plug

Former User

I think the unplugged connector is for an automatic transmission, which I assume you don't have.

krysted9354

yeah i have manual,


so what u guys think is the problem ?? can i run wire from ecu straight to the relay ?


or can the ecu be broken ? can i fix it ?

Former User

Is the critical ground wire attached to the thermostat housing clean and tight?

team_lunatics

man, i'm having the exact same problem......my fuel pump doesn't prime up when key is turn on (II)...maybe distributor or what....

watisjdm

there is always the chance that the fuel pump is locked up