bigport 4AGE takes a couple of tries to start

[rke_011]

Car - KE10

motor / part in question - 4AGE bigport

problem - Without fail the car will take 2 or 3 tries to start.. does not matter how long i try to turn it over the first time it wont start... when it eventually starts it starts quickly (usually the second or third time).. will only turn over few times then start easy.

Fuel pumps turn on only when ignition is turned completely on (running relay) but cant get it to prime before starting.

I dont believe the fuel pump is the issue, because when i turn it off it has the same issue again.

Any ideas where to start looking?
Uploaded video at -

occurs/started when (if applicable)- I fitted the motor

personal situation (if applicable)-

[pt_y2k]

Check for spark on your first attempt at starting,make sure it's good and strong...could possibly be fuel pressure too,bad pump taking a bit longer to get up to pressure...doubtful but possible.Check spark and let us know...

[maxhag]

Could be fuel pressure......
Do you have a one way check valve in the fuel system?

[Matt]

Do you have the starter wire spliced into your fuel pump relay? Plus also hooked into the STA pin on the ecu?

Big port ecu's prime the pump when the ignition is turned on.

[rke_011]

Cheers for your opinions.
I will have to check the spark when I get a moment, I did consider that but why would it not spark as much on the first attempt? it seems strange...

what is a "Do you have a one way check valve in the fuel system?" - again, wouldnt there be enough fuel in the system from it running to start straight away after it has been turned off?

I have the fuel pump connected to a circuit open relay and followed instructions i found on a site with how to set it up... fuel pumps turn on.. but have to crank it for it to turn on.. so it does not prime before starting..

Will look into spark first i think

cheers

[maxhag]

The one way check valve, holds fuel pressure when the car is not running. So, yeah, there WILL be fuel in the lines, but the fuel pressure is not yet at the required pressure to run, untill you have cranked it a few times.......



Also, if you are using the Starter wire to give signal to the relay, obviously, it will only trigger when the key is turned to the "START" position, and not ignition power, therefore, it wont prime the pump when you turn the key to ACC... This is what it is designed to do...

[Matt]

Bigport ecu's do prime the pump when you turn the ignition on. Something in the ecu earths out the fc pin temporarily.

Might only be the fwd ecu's that do this but the last 3 I've done do this.

[rke_011]

So I had a quick play around with earthing my leads to check spark... seems OK.. is there a more accurate way of checking?
Also I have noticed you literally only have to flick it over the first time to turn the motor over.. I'm talking a real quick turn .. starter barely turns over and then next turn it will start... seems strange

[maxhag]

^^ can you explain that better?
What is "flicking over"?
First you say its quick, then starter barely turns over.....
Made no sense....

[rke_011]

All good.. I fit a bypass switch in to prime the fuel pumps before starting... and now its all good..