Anyone fitted RS4 fuel rail after stage 2+ Revo?

warren_S5

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Saw a thread where a guy was having a few issues with HPFP. Thought it may be interested for those who have just had INTERNALS (e.g. not APR full pump installed). Link to thread here: LINKY

Has anyone else on here fitted the RS4 fuel rail on their S3 8P?

Also, does anyone know where the OEM fuel filter is located?

Thinking of doing this mod when I get back from Germany in a few weeks time. Need to get up to Revo when I get back so they can set up the map to accommodate.

Thanks in advance

Warren
 
Are you talking about the RS4 fuel return valve here? If you are then here are my thoughts...

I've not done the mod myself as I am only stage 1 at the moment. My understanding is that this mod will potentially help you no matter which HPFP you have installed (APR, Autotech etc).

The theory goes like this - The OEM fuel return valve opens at 130 bar and allows pressure to drop to 127 bar,then it starts building pressure back up again until it reaches 130 bar at which point the cycle is repeated.. The RS4 valve does not open until the pressure reaches 136 bar and allows the pressure to drop until it reaches 130 bar before it starts building the pressure back up.

So a stage 2+ map requests 130 bar of of rail pressure therefore this mod should be beneficial to you as it will help you maintain 130 bar fuel rail pressure rather than fluctuate from 130 - 127 bar with the OEM system. Before spending any money I would thoroughly log block 230 with VCDS to see if your rail pressure is actually fluctuating to see if you would benefit from the RS4 valve.

I do not think REVO would need to make any changes to your map to accommodate this mod imo.
 
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Cheers for the heads up.

Clutching at straws trying to resolve issues after a particularly unfruitful visit to a midlands based tuning house :sadlike:

Don't suppose you know where the fuel filter is located?

cheers

Warren
 
Hey Warren try giving Ben at AVP a call, he writes for Audi mag in the technical section and is extremely knowledgable... 01283 548 483

Got to be worth a try.
 
The fuel filter is located on the bottom left hand corner if you are facing the engine just infront of the water jet bottle - its a long life filter
 
Assuming the S3 is the same as the GTI it should be located under the car just forward of the right rear wheel.
fuel_filter-overview.jpg
 
Car is getting 'Ringed' on Friday, so want to resolve any little issues before I go.

Service today (& a diagnosis).

Wheels being refurbed and refitted tomorrow.

Thanks for all your comments guys.
 
The fuel filter is at the rear as KRL said, have been under my car quite a few times and spotted it quite a few times.

Heres the RS4 fuel pressure reg. on ETKA

rs4fuelregulatorvalve.jpg


Cheers Davie
 
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Just bought this along with some ik24 plugs in preparation for stage 2+ on Monday, looks a right tw@t to fit though, can anyone confirm?
 
Just bought this along with some ik24 plugs in preparation for stage 2+ on Monday, looks a right tw@t to fit though, can anyone confirm?

Yes this is very tricky to fit, you will need to take the fuel rails off, and make sure in the process you dont chip/crack the vacuum pipes or their clips, my mechanic found that out the hard way lol.
 
Nightmare! Thanks for the heads up Haz
 
Sorry to drag this up! has anyone fitted these at home and any tips? think i need one as my is making a few noises! Cheers
 
I got one fitted when i got my stage 2+, the garage said it was a pain and had issues with threads being a touch different but all fitted and working fine now
 
I have bought one and attempted fitting last night along with the HPFP but to no avail - IMO to do the job properly and safely, the inlet manifold has to come off! :(
 
The only difference you will see is a smoother power curve as there will be less of a flat spot around 5-6k rpm. Thats my experience anyway.
 
Had one fitted on mine as std valve had started to become noisy on light throttle. Mechanic fitted it without removing fuel rail or manifold, just a bit fiddly, took about 45mins. Never noticed the slightest bit of difference on mine tbh!
 
Had one fitted on mine as std valve had started to become noisy on light throttle. Mechanic fitted it without removing fuel rail or manifold, just a bit fiddly, took about 45mins. Never noticed the slightest bit of difference on mine tbh!

It can make a difference on some Stg2+ cars,but would become neccessary on any big turbo conversion,especially those running stock injectors.