I've got an st engine in a Ka believe it or not and the loom has been made standalone by a friend it runs but the pump runs constant and Imrc
operates fine but regarding the pump driver module does it operate as normal or?
I've checked all the pins on the module and they go where they should go. I've tried to check pin 1 is indeed switched earth but I
don't think I'll see that without an oscilloscope.
Just after a bit of guidance we seem to of overcome all but this problem.
That's the diagram I have stored and all pins go to their corresponding locations. I've checked the pins on the pressure sensor on the
rail and there also correct. I believe pin 1 and 7 on the pump driver to be canbus signals.
In running a cosworth intank fuel pump out into a 3 port fuel filter with a pressure reg built in then out to the rail
Just can't figure out why it just pumps constant and has no prime etc. When you do your modified looms do you just wire it as per how it was in
focus's and how do you do you fuel piping?
Appreciate the guidance I read the whole thread hoping to find my answer but unfortunately didn't
Yes when I do a loom I take all the covering of and trace it back as far as I can. I don't think the driver has anything to do with canbus ?
Canbus is a high speed communications port. One ecu talking to another. Even the dash doesn't use Can it uses the slower bus.
The St170 is a returnless or dead head system. There is no fuel regulator. No return to the tank. There is a fuel damper. The only real difference
between an st pump and an external pump is a one way check valve. I've took one to bits to have a look. In fact I nicked the check valve from
it and put it on the Bosch style external pump.
Oh right, so if I understand you correctly the 2 pins connected to the ECU which are pwm would be used to control the speed of the pump?
The reason I put the pressure reg there was because we don't know what's causing my pump to run all the time and that made it semi
returnless
We're just struggling to find out why it's not operating as it should and just constantly running the pump, it doesn't prime either.
I guess what Im trying to ask is do you just use the pump module wired in as per the focus would and will it regulate a normal pump or will it only
switch it on and off?
Thanks again. This the last hurdle I've got to overcome and I don't seem to be getting anywhere
I just wire every thing as it would be on the donor, chopping out any thing I think I can that won't be needed.
I no longer have access to good test equipment like an oscilloscope but my"feeling" is the pump will be pwm controlled instead of an
on/off action.
But I don't know every thing and I am happy to be corrected if any one finds differant.
Again having butchered a few st pumps I found nothing special. It's just s motor.
One thing I found is the fuel rail pressure sensor can not be read on obd2 and the ecu controls the controller based on the fuel pressure sensor and
other things.
I would check the wiring, change the fuel pressure sensor sensors and get rid of the fuel regulator.
Wiring checked and found a wire not correct so now it is as per focus the pump now stutters and shudders for a couple seconds then shuts off as if
it's done a prime but it's not operating correctly still. Can't understand why it won't run smooth for a prime then power up
again under cranking.
Do you have a feeling the vw 3 bar filter would cause it to stutter and judder? I can test it without if you think so. I just thought it was the pwm
causing the stuttering/judder
I have a cosworth in tank fuel pump this isn't the issue
The fuel filter I fitted is a vw/Audi 3 port filter which has a built in 3 bar fuel pressure regulator. It made the system semi returnless but I think
your gonna say yes that'll be my problem because it's got 3 bar up it all the time the pwm can't control it ?
I am not saying that is the problem but your saying that's the only thing not to Oem standard. Are you getting any obd2 codes to point you else
where ?
Tonight I've removed the pressure reg filter and fitted just a normal fuel filter and tested it. Low and behold it primed and ran there is still
a small judder of the pump on prime but it's loads better! Was yours a smooth prime?
Believe it or not I know my obd port works but I bought 3 code readers which aren't compatible with the st. Im bound to have codes because
certain things aren't there anymore but all engine sensors are there and believed working
Ok so pin 3 is good
Pin 10 goes from the pump to the inertia which means it's using it then goes to the pump
I'll try the obd reader again as the man who did the loom was reading sensors from it when we first did it.
The prime works just stutters ever so slightly for some reason but it revs freely and comes off cold start fine and Imrc is fully functional
