RS4 Fuel return valve

[tautvydasv]

Better watch out with that autotech fuel pump, mine seized up requesting 127bar after about a year of use. Hopefully it's one of the newer versions, I had version 2.

Around 70 000 miles including 5 track days and running fine.

[LEWXCORE]

Around 70 000 miles including 5 track days and running fine.

some seem more fortunate. Just saying- it's well known that the failure rate is high on those.

[Jimrobbington]

Hate to be a noob reviving a thread, but this had recently been found as a problem over on the Audi A4 2.0 platform. Any updates?

I am running into fueling issues, but not fuel cuts. It seems very early 2.0 A4s (05.5-06) came installed with only a 116 bar fuel rail dump valve. Awesome. I am only REVO stage 2, but it seems this may be causing issues.

It seems you guys are only aware of the OEM RS4 valve as a replacement, but there are better alternatives recently available.

hpfpupgrade.com has a 142 bar valve for $100 and you can upgrade up to 150 bar for another $25.

Any thoughts?

[crew219]

Hate to be a noob reviving a thread, but this had recently been found as a problem over on the Audi A4 2.0 platform. Any updates?

I am running into fueling issues, but not fuel cuts. It seems very early 2.0 A4s (05.5-06) came installed with only a 116 bar fuel rail dump valve. Awesome. I am only REVO stage 2, but it seems this may be causing issues.

It seems you guys are only aware of the OEM RS4 valve as a replacement, but there are better alternatives recently available.

hpfpupgrade.com has a 142 bar valve for $100 and you can upgrade up to 150 bar for another $25.

Any thoughts?

Lol.

It's not better when the programming doesn't ask for anything more than 130 bar.

[Jimrobbington]

True, but if I dump at only 116 bar, there is much room for improvement.

Anybody know what stage 2 REVO fueling 9 requests for fuel pressure? I wish I had a vag com.

[GolfRS]

True, but if I dump at only 116 bar, there is much room for improvement.

Anybody know what stage 2 REVO fueling 9 requests for fuel pressure? I wish I had a vag com.

129.9 bar

[Jimrobbington]

129.9 bar

If thats true, I'm missing out on close to 200 psi of fuel. Thats a pretty drastic difference, as long as my stock hpfp can handle the 130 bar.

[GolfRS]

Your stock pump cannot handle 129.9 bar especially at peak boost.

No matter what the software requests.

That is the reason for the aftermarket HPFP's existence...

[shiro1745]

Lol.

It's not better when the programming doesn't ask for anything more than 130 bar.

Could you elaborate a bit? I'm in the market for a rail valve and not sure which one to get the rs4 136bar or the 142 bar from hpfpupgrade

Are there any drawbacks by getting the 142bar valve if I'll stick with the stage 2+ ?
I might go BT in the near future so if the 142bar would be better I would just get that one now instead the RS4 and replace it in let's say 1 yr

[GolfRS]

Could you elaborate a bit? I'm in the market for a rail valve and not sure which one to get the rs4 136bar or the 142 bar from hpfpupgrade

Are there any drawbacks by getting the 142bar valve if I'll stick with the stage 2+ ?
I might go BT in the near future so if the 142bar would be better I would just get that one now instead the RS4 and replace it in let's say 1 yr

What he means is if the program only asks for MAX 130 bar, the limit of the valve will never be reached
regardless.From my experience though that is not 100% correct.A have seen values of +5 bar from requested and not at throttle off...

On the other hand, raising or running higher pressures puts more strain on the cam follower and cam.
If you don't understand this or are not aware what the consequences are, it's better you stick to
stock valves....

[shiro1745]

What he means is if the program only asks for MAX 130 bar, the limit of the valve will never be reached
regardless.From my experience though that is not 100% correct.A have seen values of +5 bar from requested and not at throttle off...

On the other hand, raising or running higher pressures puts more strain on the cam follower and cam.
If you don't understand this or are not aware what the consequences are, it's better you stick to
stock valves....

I have to find out what APR 2+ is requesting, I'll probably get some logs tomorrow if I have time. I've heard people saying that A4 B7 05.5 & 06 have the old 116bar(i think) rail valve which would be my case. So my question is if I get the 142bar valve and only run APR stage 2+ would it do any harm? Basically why not get the better one just in case I decide to go BT soon and this would be a must.

I must say that I'm not even close to be an expert but I'm willing to learn as much as I can. I've had the car for 3 years now and knew nothing about engines before, I've always liked cars though and I'm mechanically inclined. I have all the mods for stage 2+ which I installed myself. In the last couple years I've learned a lot compared to nothing but I still consider myself a beginner.
So my question now is what exactly do you mean by consequences? I understand the follower and cam lobe would wear faster but I've had my follower along with HPFP and cams replaced about 6k ago under warranty and I'm planing to check my follower every other oil change (3k miles). Was there anything else you meant there?

[viziers]

I have to find out what APR 2+ is requesting, I'll probably get some logs tomorrow if I have time. I've heard people saying that A4 B7 05.5 & 06 have the old 116bar(i think) rail valve which would be my case. So my question is if I get the 142bar valve and only run APR stage 2+ would it do any harm? Basically why not get the better one just in case I decide to go BT soon and this would be a must.

I must say that I'm not even close to be an expert but I'm willing to learn as much as I can. I've had the car for 3 years now and knew nothing about engines before, I've always liked cars though and I'm mechanically inclined. I have all the mods for stage 2+ which I installed myself. In the last couple years I've learned a lot compared to nothing but I still consider myself a beginner.
So my question now is what exactly do you mean by consequences? I understand the follower and cam lobe would wear faster but I've had my follower along with HPFP and cams replaced about 6k ago under warranty and I'm planing to check my follower every other oil change (3k miles). Was there anything else you meant there?

What he means is that as of now the HPFP runs at say 120bar which results in applied pressure to the HPFP plunger down to the CF and to the cam.. Now add another 20bar and you are putting that much more pressure the the plunger,CF & cam resulting in faster wear on the critical components... But if you do the CF checks regularly theny ou should be ok....




vizi

[BlueDevil504]

Can anyone tell me what the torque spec is on the fuel return valve - thank you

[eMiL-R]

Hey, Im bumbing this thread again!

Does anyone have a DIY guide for this operation, or know where i could get one?
Don't know if im going to try to change the valve without talking the manifold away or not..

[Jimrobbington]

Hey, Im bumbing this thread again!

Does anyone have a DIY guide for this operation, or know where i could get one?
Don't know if im going to try to change the valve without talking the manifold away or not..

It really is possible without removing the manifold. I have done it twice. You just need some crows feet and a ratchet extension. I think its a 14mm and a 17mm. Should take around an hour. Hardest part is threading the new one on. You will need electrical tape and patience.

[eMiL-R]

It really is possible without removing the manifold. I have done it twice. You just need some crows feet and a ratchet extension. I think its a 14mm and a 17mm. Should take around an hour. Hardest part is threading the new one on. You will need electrical tape and patience.

Thanks a lot for the answer!
I think i will try to make it without removing the manifold. What's the electrical tape for?
Patience is not really my strongest side but i'll give it a try!

Will also try to make a DIY for this one.

[Jimrobbington]

Thanks a lot for the answer!
I think i will try to make it without removing the manifold. What's the electrical tape for?
Patience is not really my strongest side but i'll give it a try!

Will also try to make a DIY for this one.

You will have to tape the valve to the extension in order to get it threaded back on.

[eMiL-R]

Oh is it that tight. This is going to be fun to try, wish me luck!

[eMiL-R]

You will have to tape the valve to the extension in order to get it threaded back on.

I think i need a better explanation on how to go about it haha. I pick off the fuel lines so I can push them to the side for better access.
Is it supposed to keep the crows feet above through the small hole just above the valve or which way should i go?

Please give me some advices )

/ Emil

[S3Power]

Hello people!

I have a problem with the fuel pressure (Revo Stage 1).

You may be putting RS4 valve is fixed?


With file V3 (Revo Stage 1) had these pressure drops.

V3 (127b):



Revo dealer remap my ECU with the latest version of Revo file (V11) and I still falls.

V11 (124b):



- I've checked the camfollower and well (I've changed for a new one).

- New fuel filter.

- Lobe Cam in perfect condition.

Car: Audi S3 (BHZ)

Regards.

[bacillus]

What hpfp are you using?
Also have you logged your in-tank lpfp to see if it's keeping up the requested bar?

[S3Power]

What hpfp are you using?
Also have you logged your in-tank lpfp to see if it's keeping up the requested bar?

Hello.

HPFP is the stock. In theory a Stage 1 (Revo) is for stock cars.

I show a log of channel 231 (vagcom).



The car (Audi S3 BHZ) has 52,000 km and only is one month reprogrammed.

Thanks!