[Mk2] [Turbo] **FIXED** *NO fuel coming out of return fuel rail line!

[jimGTS]

test injectors

come across a similar problem (diff car though) and it was the ignition pump.... costly!

ive tried both my 850s and new 540s in the car, so chances that both injectors are duff is unlikely.

[justarn]

hey my ecu injector resistors went, no engine codes drove me mad! not read the whole post but i had the same synptoms. i put another ecu in an it blew them in that too then the third ecu's stilll goin! got the ecu diagnosed and reconditioned by dave patric's in sittingbourne! jus a thought!

[jimGTS]

Ok hooked up the pressure gauge, only getting 10psi on idle and revs. Fp and b+ bridged.
I thought pressure moves up and down when revving??

Either way about 10psi on the inline, between fuel filter and banjo.

Fuel pump for sure??

[Martin F]

Ok hooked up the pressure gauge, only getting 10psi on idle and revs. Fp and b+ bridged.
I thought pressure moves up and down when revving??

Either way about 10psi on the inline, between fuel filter and banjo.

Fuel pump for sure??

would say so mate, mine is saying 50 just by putting the ignition on, be a bit gutting if this was causing all your problems and you didn't need a new power fc etc.

[jimGTS]

Gutting for different reasons really.
It wernt as if I was waiting all this time for a powerfc to turn up to start my checks.
Was doing tons of checks throughout that time and to have same issues on stock ecu so it's kinda obvious it wernt power fc. But had to get one anyway incase it was.
Can still sell the new one for good money either way.
Either sell old one and use brand new one or other way around.

So does yours stay at 50 and eventually go down to 30ish when warmed up??

[Martin F]

Gutting for different reasons really.
It wernt as if I was waiting all this time for a powerfc to turn up to start my checks.
Was doing tons of checks throughout that time and to have same issues on stock ecu so it's kinda obvious it wernt power fc. But had to get one anyway incase it was.
Can still sell the new one for good money either way.
Either sell old one and use brand new one or other way around.

So does yours stay at 50 and eventually go down to 30ish when warmed up??

Not sure jim as i have never studied it, sorry

[Andy F]

We set fuel pressure at 40psi at tick over, with a rising rate FPR it will
increase with boost

[jimGTS]

We set fuel pressure at 40psi at tick over, with a rising rate FPR it will
increase with boost

Confused??

I asume your responding to martys 50psi Base fuel pressure?

Got any info for me?? Lol.
Fuel pump issues in your opinion?

[Andy F]

You need to be measuring fuel preasure from the FPR .

The FPR acts as a thumb over the end of a garden hose!

So FPR on the return side??

I havent read the whole thread Jim so im not sure where your at

[jimGTS]

You need to be measuring fuel preasure from the FPR .

The FPR acts as a thumb over the end of a garden hose!

So FPR on the return side??

I havent read the whole thread Jim so im not sure where your at

by from the fpr, what exactly do you mean??
Fuel pressure is ment to be measured before the rail surely?? There is no other way of measuring pressure surely? Going by your thumb over the hose example it is that pressure in that hose your measuring, ie before the fpr, ie at the inlet side.
Pressure out of the rail I've been told doesn't tell you anything about fuel pressure as it's just a return line to the tank. Bgb also tells you to measure on the banjo on the inlet side. Ie basically what I've just checked.
Just trying to understand what your saying.

Cheers

oh and btw, I Imagine Im near to 0 psi on the outlet side of fpr as NO fuel is coming out the return line.

[Martin F]

edit

[jimGTS]

edit

I was gona say, I saw what you wrote.
So either way dude. Start of the rail or end of the rail Where the fpr is should read same fuel pressure.
From what I gather once it sees over x psi, regulator opens and sends fuel back to the tank via that return pipe.
I think.

[Andy F]

Jim the FPR closes as boost rises
This is how mine is set up
The bowl thing is were my electronic fuel gauge is connected

The hose coming from the side comes from the fuel rail (return) and the bottom returns to the tank
The blue pipe goes to the manifold for boost preasure


Have you adjusted the FPR with the nut and bolt?

[jimGTS]

Andy all I'm seeing there is just your fpr further down the line?
That is still a stock setup tho right?? You just can adjust your base pressure.


The pressure going into your fpr is still the same way I've measured my fuel pressure, before the fpr. I've just got my presure readings before the injectors whereas yours is after injectors. Still should be same presure across the rail right. Unless you got a presure drop.

I'm using a stock fpr btw, I've swapped in 2 different rails with there own oem fprs, same issues so isn't a fpr issue.

What do you have going on at the drivers side end of the fuel rail?
Is your rail aftermarket??

Cheers

[Andy F]

Its a HKS fuel rail and FPR...

Drivers side goes straight in from the pump (intank)

I do think you need measure preasure after the rail, if you imagine our hose pipe with 4 little holes in it, the preasure before the holes will be less than where your thumb is at the end

So which rail you got in now??

Also i read a couple of pages from the very start, when you were swapping ecu's....you said your injectors were high imp?
Was you rewiring the resistor pack things when ever you put the rev3 ecu back on?

[jimGTS]

No I only rewired resistor pack when I finally got hold of some 540s which came in a rail, so easy enough swap.
Some of these tests I did use rev3 ecu with the 850s and bypassed resistor pack.

But issues are the same before and after this injector swap and bypassed and unbupassed resistor pack.

Either way with NO fuel going in my return line dude, I'm not going to see any pressure surely?? So pointless trying to measure pressure there with no fuel in that line?? Maybe a few psi at best?

[Andy F]

Yer im with you now Jim

It has to be the pump, did you get round to changing it??

I went for the Supra pump..reliable

[jimGTS]

No not yet, but I've bought a high pressure walbro 255 one to pop in.
Ryan (2bar tuning) think I have a Bosch pump in there at the mo. Sounds the same as the 2 phoenix cars he's mapped. Both those had Bosch pump. And this is definatly loader than my walbro I had in my old rev2.
So it's this that has potentially died. Or is leaking under pressure.

Just hope I can simply swap in the walbro and I don't come across loads of custom lines that I cant mate it up to.
That would be a royle pita!

I'll keep the gauge on there for time being
just spent this past hour taking off the heatshield! Pita trying to get that out with my top mount turbo in the way. Thankfully finally cone out and I'll have decent access to the tank lines when I come round to swapping out the pump with a kind chap from the oc who's going to give me a hand.

What a mission! Just hope it IS the pump that has been causing me all this grief!!!

[Andy F]

It has to be matey!!

hope the 255 isnt the great big one like Chris used
that was a big pain , new fittings wiring and the + - terminals were
marked up wrong so it all had to come back out to swap them over

[jimGTS]

The 255 is the smallest of the walbro options. They have 305 and 345 to.
Tho I be there custom installs.

The 255 should be plug and play, my last walbro was on the rev2.
This one is just a high pressure version, now I can't be sure every 255 walbro out there is the high pressure one, maybe just isn't labelled as high pressure.

Should be plug and play! Bloody better be. Only have a 400hp goal, 255 walbro ment to be rated to 500hp so I should be fine.

Just hope I have no issues fitting it!