what is this relay 4

[The Witzl]

maybe its just the airflow ones! but i know the map ones do or at the very least the 4ag small ports do.

I will confirm with you that they DO NOT.

I think what peewee means by pre-prime is when the fuel pump is turned on for a second or two when you turn to ignition BEFORE cranking the engine.

I will state UNDENIABLY and furthermore can irrefutably confirm that no 4A pre-primes the fuel pump in this manner.


They do however do the following:

# On cranking the starter motor, the first coil in the Cir. Opening Relay is energised and closes the relay contacts, running the fuel pump whilst the starter motor is turning over the engine.
# If the engine jumps into life (ie- ECU is getting ignition signals), the ECU switches the transistor controlling the "Fc" output to ground on the ECU.... which is of course connected to the second (normal) coil on the Circuit Opening Relay, in turn energising that coil and keeping the contacts in the relay closed (and thus the fuel pump running)
# If the ignition signals to the ECU cease, the "Fc" output on the ECU is opened (switched off) after about 2-3 seconds.

It's all in the wiring diagrams peoples, think about it!

[kingmick]

I will confirm with you that they DO NOT.

I think what peewee means by pre-prime is when the fuel pump is turned on for a second or two when you turn to ignition BEFORE cranking the engine.

I will state UNDENIABLY and furthermore can irrefutably confirm that no 4A pre-primes the fuel pump in this manner.


They do however do the following:

# On cranking the starter motor, the first coil in the Cir. Opening Relay is energised and closes the relay contacts, running the fuel pump whilst the starter motor is turning over the engine.
# If the engine jumps into life (ie- ECU is getting ignition signals), the ECU switches the transistor controlling the "Fc" output to ground on the ECU.... which is of course connected to the second (normal) coil on the Circuit Opening Relay, in turn energising that coil and keeping the contacts in the relay closed (and thus the fuel pump running)
# If the ignition signals to the ECU cease, the "Fc" output on the ECU is opened (switched off) after about 2-3 seconds.

It's all in the wiring diagrams peoples, think about it!

if i turn the ignition on my rolla when it had the standard ecu it would pump for a few seconds{i could be wrong even on this as its been awhile}. ill check the soarer when the wife brings it home next week.
lol its hard to remmeber factory stuff when you have been using aftermarket ecu's and nothing else for so many years.

[JustCallMeOrlando]

Yep, I guarantee thats how Peewee was reading it.

[kingmick]

thats how i see it! as we do the same with the race engines!

[The Witzl]

yeah most (i think all?) aftermarket ECUs run the pump for a second or so when you turn the car to ignition..... so it's easy to be confused if that's what you are used to

[CrUZida]

Most Nissan ECU's will pre-prime for 10-15secs when you switch the ignition on too.

[AE86slut]

yeah most (i think all?) aftermarket ECUs run the pump for a second or so

*Slaps forehead* Of course...

[The Witzl]

*Slaps forehead* Of course...

*slaps jeremy's forehead for being a douche*


douche

[AE86slut]

*slaps jeremy's forehead for being a douche*


douche

Thanks Karl... I totally deserved that

*Slaps Karl's forehead for driving a yellow car*

[cambelt]

looks like i started a debate , hehe