Faulty fpr???

[milkandoj]

His explanation makes sense if someone who is searching on the topic or still figuring it out. Most people like a reason why to do things.

I asked razza who wrote the chip for the 510's he said to run them at stock vr4 pressure coz that what the chip was written at. Hope this isnt wrong...

 

[andy's-galant]

Maybe 510's can run at stock vr4 fuel pressure but not the 560's.
Im not setting it wrong i have a fault somewhere.
Over on galantvr4.org someone mentioned fuel pump, could this cause any of this?

 

[omad]

The chips are usually set by the injectors specs for cc flow and deadtime. For an evo 510/560cc those specs are rated at the ~42psi. Whether the 510's off a VR4 are different, I'm not sure. But basically if you set the injectors at the wrong base pressure they are going to perform outside their rated specifications.

 

[milkandoj]

The chips are usually set by the injectors specs for cc flow and deadtime. For an evo 510/560cc those specs are rated at the ~42psi. Whether the 510's off a VR4 are different, I'm not sure. But basically if you set the injectors at the wrong base pressure they are going to perform outside their rated specifications.

Yeah mate of course.
I did ask the chip writer and he said stock vr4 pressures for the 510 chip.
Im thinking it might be 42, could explain my top end knock when i wound the boost up while logging. Thats why i been running gate pressure till i get off my ass and figure out how i wired my wide band wrong.

End of hijack!!!

 

[milkandoj]

Another random theory..
Are you taking any other pressures like boost gauge or boost controller off the line for the FPR.
Its one of the more reliable scource so many people do this, including me.

However if you had a leak in the long line heading throught the fire wall it could send the FPR's pressure up the shite.
Thats why ive thought myself if its really a great idea.

 

[Entaran]

milk, that's really good thinking. Hope it leads to something.

For the record, my boost gauge is tee'ed off the compressor housing vac line. I think it's just as accurate as the FPR line without actually cutting the FPR line.

 

[andy's-galant]

Ok guys this is getting frustraing, im going to put the stock vr4 fuel pump in to see if its my pump playing around, i think that would be the first thing i should try right?

 

[Entaran]

When you do it, run new (temporary) power and grounds for it. That way you can also rule out wiring bouncing around and shorting out at random.

 

[brisvr4]

When guys like Keydiver write you a chip they will ask what base fuel pressure that you are using and will compensate for it in the chip. You really don't need to run 42 psi ( which is actually lower than the 43psi that evos run stock vs 37 for VR4's ) as long as the chip is setup correctly.

Most injectors are tested and rated at 43 psi anyway.
I ran my 560's at 37psi base with no problems at all.
Saying you will blow up your motor by doing this is a bunch of horse crap!
You just need to have everything set up correctly to start with.

BTW, if you have a fuel pressure gauge attached to your fpr in the engine bay make sure you set the fuel pressure COLD as the gauge WILL READ WRONG once the engine bay gets hot enough to heat the liquid in the gauge.

Also, the lower you can have your base fuel pressure the easier it is on your fuel pump as it doesn't need to work as hard on boost.

 

[andy's-galant]

Chucked the stock vr4 fuel pump in earlier and now it doesnt boost past 4000rpm
Im going to do leak test when bunnings opens again. I think i got a leak or a faulty bov, i have the evo8 plastic bov on and i tryed an atmo turbosmart bov and still doesnt boost past 4000, in 3rd it keeps going past 4000 but stutters and really slowly revs past 4000.
Would i be right in saying this sounds like a faulty bov or a leak? Or is it something more technical like the ecu, or faulty injectors?

I did notice the car idle much better and before it hits 4000rpm it sounds and goes good, but then just stops.

Btw Tim, i got Miodrag to write the chip for the 560's, and was told 41psi would be good to run, and i set the fpr when the car is cold today, but havent been taking that into consideration in the last two weeks when i adjust it.

 

[brisvr4]

OkAndy, If Miodrag has set the chip up for 41psi then run that mate.
You might want to get him to perhaps write another chip in case there is something missed in the old one...
I think someone up here has my old 560 chip, I'll ask around and see if I can find it for you to try if you like.

 

[andy's-galant]

Ok i will contact miodrag and discuss it, so could having the chip not set correctly cause this problems? We did have abit of confusion as to where meek had first set the chip and what miodrag recommended, sorry i dont understand too much about the ecu side of things.
Ok another chip to try would definately help, i can fix it up Tim Or ill see what midrag can help with.
I think next thing is to do is intake leak test.

 

[andy's-galant]

The car wasnt passing 4000rpm due to the stock vr4 fuel pump, i now have the walbro back in.
Ive today done a leak test and found to have a big split in the bov vacuum hose(manifold end)
Also bov is leaking bad, i tryed a bov of my sisters car and after putting the walbro back in the car seemed fine, though i didnt get to drive it far.
My walbro makes different noises, today for starters it was like a constant wistle and then it started whing like a siren, is this normal for the pump to make this noise? I have also heard that they are loud but never thought this loud, in my sisters gtir she has a walbro and i can hardly hear it.

 

[mannynz]

The more resistance it have to flow the more noisier it gets.

You might want to check your fuel filter.

 

[andy's-galant]

Ok second person to mention fuel filter, how often are they meant to be changed? I will change it within the next couple of days, its been close to 1 year since changing the fuel filter.
Also will a evo 8 or 9 fuel pump work with my mods? Does anyone have feedback on this, will my car too lean or to rich etc? I just cant afford a bosch right now

 

[brisvr4]

As I said over at gvr4.org you don't need to change from your Walbro.
You are just making more work for yourself.
The Walbro will be fine with your turbo and injectors. It will and does feed much larger setups than what you have right now.

 

[andy's-galant]

Ok picked up a bov today and took the car for a drive and it is running well, ill have to see on a much longer trip to reconfirm if its all good.

 

[mannynz]

[quote name='andy's-galant']Ok second person to mention fuel filter, how often are they meant to be changed? I will change it within the next couple of days, its been close to 1 year since changing the fuel filter.[/QUOTE]

It do not need getting replaced that often.

I have seen people installed the wrong type of fuel filter where flow capacity is much lower than what the engine requires.

 

[andy's-galant]

Oh fair enough, i will change it anyways along with my spark plugs, i usually try to change things before they are due.
So how long does fuel filter go for?

 

[Entaran]

Until you cop a bad tank of fuel or 2 yrs.