My 400bhp Sprint Blue Sportback S3

[cupraraj]

Hello,

I've come from a BMW background and bought an S3 a few months ago. I was always going to get sportback and S-Tronic and I either wanted Sprint Blue or White. This came up and had the pan roof and S-Tronic but it had been modded which I wasn't keen on but after I drove it I ended up buying it!

The mods are:

- Full Miltek Turbo-back Exhaust
- LOBA HPFP
- TTE 420 Uprated Hybrid Turbo
- RS3 Intank Pump
- VW Racing Intake
- GIAC DSG Flash
- Stage 2 Re-map

After a couple of months it started playing up and when I would put my foot down it would kind of get jerky and push back abit...the power definitely isn't there like it first was and a scan on VCDS came up as P0087 - Fuel Pressure Too Low

I have read it could be HPFP related or something but the LOBA was only put on the car 6 months ago and took it to the local specialist and they need it for a day or two to diagnose.

Does anybody recommend a good specialist in West Midlands area?

Cheers

 

[Hookmonster]

Rs4 fuel return valve ? Could do with one..


Is that your full list of specs ??

 

[S3Alex]

Welcome to ASN.

Best man in roughly your area would be Rick @ Unicorn.

It's quite possible that either the rail pressure is causing issues and an RS4 valve may help or that the LP fuel pump need some mapping for the power level you're running.

Some tuners have had problems getting the RS pump working properly with the stock controller on the S3.

 

[cupraraj]

Rs4 fuel return valve ? Could do with one..


Is that your full list of specs ??

Yeah but even at low revs its abit lumpy with the power like it dont want to boost properly. When i had it first it was an animal and drove really good.

What do you mean full list of specs? Mods you mean?

 

[cupraraj]

Welcome to ASN.

Best man in roughly your area would be Rick @ Unicorn.

It's quite possible that either the rail pressure is causing issues and an RS4 valve may help or that the LP fuel pump need some mapping for the power level you're running.

Some tuners have had problems getting the RS pump working properly with the stock controller on the S3.

Thanks. Will do some research on uni-corn. I took it to midland VW who mentioned something about mapping the rs3 intank pump but havent had time to drop it back to them. The car still drives fine you just cant thrape it.

So is the rs3 intank pump the lpfp?

 

[S3Alex]

Thanks. Will do some research on uni-corn. I took it to midland VW who mentioned something about mapping the rs3 intank pump but havent had time to drop it back to them. The car still drives fine you just cant thrape it.

So is the rs3 intank pump the lpfp?

The RS3 intank pump you have is the LPFP.
It has a higher maximum flow capacity than the stock S3 intank pump.

It needs to be mapped properly,to avoid overheating the S3 fuel pump controller,and other issues governing pressure.

This thread and a few others on VAGOC will give you some idea of the problems people have had.
http://www.vagoc.co.uk/vb/showthread.php?t=12327&highlight=lpfp

Basically don't thrash it until this is sorted out,as the last thing you need is the engine going lean at full throttle.

 

[cupraraj]

had the car back from the garage. They took the hpfp off and cleaned it. removed coil packs and sparkplugs and put them back in...did compression tests and tested the lpfp also and now the P0087 codes are not throwing up anymore and car feels a lot better however there is a well known flat spot at high revs now where as before I couldn't feel a flat spot.

they did recommend the rs4 fuel valve and quoted £200 to fit...is this the going rate? and will I not see any flat spots? its funny as I couldn't tell of a flat spot first unless my standard s3 valve is weaker now.

 

[Hookmonster]

Way too much... hour job if they know what there doing..

 

[S.]

That's a bit pricey.
I guess that now you feel the flat spot because your car is in great working order again and you got the extra power back.
You can feel the flat spot on agressive stage2+ setup so i guess on your it's even more noticable.
You can get 145 and 155 bar fpr from hpfp upgrade (that's the name of the company if i'm correct) where rs4 fpr is 136 bar if i remember correctly. It costs a bit more but you may bennefit on your setup from it.

 

[S3Alex]

The concern using 145/155bar valves is the load on your cam follower and frankly you don't need that sort of rail pressure at that sort of power.

 

[RedDejavu]

Why dont you get PM3 controller? It will sort out the rs3 intank fuel pump issues

 

[S3Alex]

Why dont you get PM3 controller? It will sort out the rs3 intank fuel pump issues

I gave him some advice and links on that before,but I know Rick also has some expertise there,so hopefully between them and us it will be sorted.

 

[cupraraj]

That's a bit pricey.
I guess that now you feel the flat spot because your car is in great working order again and you got the extra power back.
You can feel the flat spot on agressive stage2+ setup so i guess on your it's even more noticable.
You can get 145 and 155 bar fpr from hpfp upgrade (that's the name of the company if i'm correct) where rs4 fpr is 136 bar if i remember correctly. It costs a bit more but you may bennefit on your setup from it.

I will be going with the RS4 one as as high as 145 I don't think ill need that much but thanks anyway. hoping maybe someone could fit it for around £100 all in or am I dreaming?

Why dont you get PM3 controller? It will sort out the rs3 intank fuel pump issues

whats a pm3 controller? I am not more power hungry I just want it to be what it says on the graph and it feels very fast now but I don't believe its to its max potential.

 

[S3Alex]

I will be going with the RS4 one as as high as 145 I don't think ill need that much but thanks anyway. hoping maybe someone could fit it for around £100 all in or am I dreaming?



whats a pm3 controller? I am not more power hungry I just want it to be what it says on the graph and it feels very fast now but I don't believe its to its max potential.

https://torqbyte.com/products/torqbyte-pm3

High power driver module for a pump such as the RS3 in tank pump.

Alternative is to use the RS PWM controller,or to use the pump system I have.

All will do the job perfectly well.

What you need to know first is what the current pump is up to....I.e. Is it's duty cycle maxed out in which case you do need an uprated LPFP.

Flat spots can be down to a number of things,and this is one of them.
Another is how well the mapping has been done,and how it matches demand to supply....the stock ECU does have some issues with high power applications(usually around the 500bhp mark) but people like Rick are up to that sort of task.

Mine had a significant flat spot,which wasn't down to fuelling(as the same setup I had then is more than adequate for the 600+bhp I can now run)but was mapping and ECU related.

I honestly think that your best bet at this stage is to involve someone like Rick,who would be capable of sorting this lot out for you.

 

[cupraraj]

I will get the RS4 Fuel Valve fitted and see what difference that makes.

Im not happy with the exhaust being a Miltek...I would of thought the tips would be chrome and have the miltek logo on the tips but they don't? I was told it should be on the silencer and not the tips now but overall I don't think the exhaust makes any difference in noise or power.

Anyone in the midlands change the tips? they are bit In aswell and would like them out abit.

 

[S3Alex]

I think the Miltek has had it's day as being the only performance exhaust for the S3.

I had been happy with mine,and even when the original back box blew a weld,they replaced it FOC,so whilst customer service is good,there are better around,such as BCS,who will be building a custom system for me shortly.

 

[desertstorm]

I use Midland VW if I have to take the car to a Garage, pretty knowledgeable and they do a good job.
http://www.midlandvw.co.uk/home.html
As stated above Rick is very good at sorting issues on these. A bit further to go, just by Manchester airport but the car will go on the dyno and it would get sorted.
https://www.facebook.com/UnicornMotorDevelopments/

 

[MICHAEL PARKER]

My BCS is really good , sounds awesome as well .

 

[S3Alex]

My BCS is really good , sounds awesome as well .

I've had a lot of conversations with Nige at BCS,and he's been extremely helpful,so I'm looking forwards to seeing what they can do for me.
My old Miltek is falling to bits right now,through no real fault of it's own,it just wasn't designed for this.

 

[cupraraj]

im going to be upgrading to R8 coilpacks and change sparks and maybe all 4 injectors as I have a very slight misfire and garage advised just change all of them at once... would I need to go uprated on the injectors with this power? or will standard injectors be able to cope?

 

[S3Alex]

im going to be upgrading to R8 coilpacks and change sparks and maybe all 4 injectors as I have a very slight misfire and garage advised just change all of them at once... would I need to go uprated on the injectors with this power? or will standard injectors be able to cope?

I'd be wary of changing the injectors if you don't need to as they are pricey.
Do the plugs and coilpacks first,and if that cures it,you've saved a good few hundred pounds.

At 400-420+ bhp,the stock injectors may max out,and need replacing with some that can flow more,such as the RS4 injectors,or Bar-Tek S3 injectors,but I haven't used those so I can really comment on them.
Mapping RS4 injectors so they don't smoke is Rick's territory.

 

[cupraraj]

I'd be wary of changing the injectors if you don't need to as they are pricey.
Do the plugs and coilpacks first,and if that cures it,you've saved a good few hundred pounds.

At 400-420+ bhp,the stock injectors may max out,and need replacing with some that can flow more,such as the RS4 injectors,or Bar-Tek S3 injectors,but I haven't used those so I can really comment on them.
Mapping RS4 injectors so they don't smoke is Rick's territory.

if Rick was closer I would of gone to him but Manchester is too far for me.

will RS4 injectors be a straight fit into my s3 and are they actually an upgrade?

 

[S3Alex]

if Rick was closer I would of gone to him but Manchester is too far for me.

will RS4 injectors be a straight fit into my s3 and are they actually an upgrade?

RS4 injectors will flow enough for 500bhp.
The problem is you need mapping specific for them to run correctly and they do tend to smoke a bit due to the spray pattern being different from S3 injectors.

They are a straight fit but as you can see not entirely straightforward.

 

[Rick @ Unicorn Motor Dev.]

You need to have logs taken to see what is causing the flatspot. Is it fuel starvation causing the ECU to reduce load as a safety feature? If so, is this due to an injector pulse width issue or a fuel pressure issue. If it is fuel pressure, is it low fuel pressure or high fuel pressure that is causin the problem?

For new injectors (if needed) - the current 2015 RS3 injectors are the ones to use.

Rick

 

[S3Alex]

For new injectors (if needed) - the current 2015 RS3 injectors are the ones to use.

Rick

Thanks Rick....that's very useful information to a lot of us.
What's the maximum in terms of bhp with those injectors?

 

[cupraraj]

You need to have logs taken to see what is causing the flatspot. Is it fuel starvation causing the ECU to reduce load as a safety feature? If so, is this due to an injector pulse width issue or a fuel pressure issue. If it is fuel pressure, is it low fuel pressure or high fuel pressure that is causin the problem?

For new injectors (if needed) - the current 2015 RS3 injectors are the ones to use.

Rick

thanks for the input. I no longer have fuel pressure codes showing up...only cylinder misfire on number 1 so I am going to change spark plugs / put r8 coilpacks in / and change all 4 injectors as id rather just do all 4 to save the hassle but my question is will standard s3 injectors be ok to put in ?

whatever is in there atm I am not sure but once I change all injectors I am going to get the rs4 fuel valve fitted aswell...is it easier to get the fuel valve fitted at the same time?

 

[Rick @ Unicorn Motor Dev.]

Alex, 600bhp should be attainable with sensible fuel pressure.

Changing to a RS4 has no effect unless you are tuned for it. It also is not required on a TTE420 if you are running RS4 or larger injectors.

Rick

 

[S3Alex]

Alex, 600bhp should be attainable with sensible fuel pressure.

Changing to a RS4 has no effect unless you are tuned for it. It also is not required on a TTE420 if you are running RS4 or larger injectors.

Rick

That's good news Rick.....many thanks.

 

[cupraraj]

changed all 4 injectors with stock ones as originally when work was done it was stock ones that were in the car as i rang up Statller who did the work.. R8 coilpacks and spark plugs and also the RS4 fuel valve fitted. Feels a lot stronger...no more misfires and a lot smoother but i am dissapoiinted with the fuel valve as i cannot feel much of a difference?

 

[S3_Sanni]

Everyone running tte420 usually go for the 155 fuel valve rather than the rs4... Should maybe ask Statler if that will help?

Sent from my SM-G935F using Tapatalk

 

[HHS3]

Everyone running tte420 usually go for the 155 fuel valve rather than the rs4... Should maybe ask Statler if that will help?

Speaking to Statller will be your best bet for sure, but it depends on how much power you're going for in the long term I'd say.

The RS4 FPRV limit is 136 bar so the 155 bar FPRV might be a better choice depending on future plans. As Alex said the latter might be a tad over kill at the moment on the cam follower so you'd have to check it more regularly, alternatively you could buy the uprated cam follower that Statller will be selling very soon on behalf of Precision who manufactur it (here's some more info on it http://www.audi-sport.net/xf/thread...logies-international-sold-by-statller.282417/)

 

[Rick @ Unicorn Motor Dev.]

Return valves are just safety valves. They do not give you anymore power directly.

 

[HHS3]

Return valves are just safety valves. They do not give you anymore power directly.

For sure, I only mentioned the RS4 FPRV as it is known to cure a flatspot around 5K on aggressive stage 2+ remaps as you know all too well I'm sure. As these boys are on the TTE, knowing the slippery slope may lead to even bigger turbos (S3Alex!) then the 155 FPRV may be a better option for them in the future whilst they're there.

 

[S3Alex]

For sure, I only mentioned the RS4 FPRV as it is known to cure a flatspot around 5K on aggressive stage 2+ remaps as you know all too well I'm sure. As these boys are on the TTE, knowing the slippery slope may lead to even bigger turbos (S3Alex!) then the 155 FPRV may be a better option for them in the future whilst they're there.

Mine has the RS4 valve,and we never seemed to have problems with that,even on the bigger turbos.

Obviously the fuelling on mine is very different now,but I don't think there is any need for some of the really high pressure valves at even up to 500bhp+

 

[HHS3]

Mine has the RS4 valve,and we never seemed to have problems with that,even on the bigger turbos.

Obviously the fuelling on mine is very different now,but I don't think there is any need for some of the really high pressure valves at even up to 500bhp+

I didn't realise that you're still running the RS4 FPRV, despite re-reading your epic build thread again over the past few days haha! In that case I have less knowledge on these valves then I initially thought, which was already very little! At what point would the 136 bar from the RS4 valve become insufficient and a higher pressure valve become necessary?

 

[S3Alex]

I didn't realise that you're still running the RS4 FPRV, despite re-reading your epic build thread again over the past few days haha! In that case I have less knowledge on these valves then I initially thought, which was already very little! At what point would the 136 bar from the RS4 valve become insufficient and a higher pressure valve become necessary?

There's several factors to consider.

Firstly,it IS possible to increase flow through an injector by increasing the fuel pressure across it,up to a limit.

However,the other limiting factors are:

1.LPFP flow capactity....on a stock S3 this is around 440bhp or thereabouts.
2.HPFP flow capacity....an uprated HPFP will still have a flow limit,but I can't recall offhand.
3.Raising the FPRV pressure may also increase the load on the cam follower and pump internals.

Rick states above that RS3 injectors are good for around 600bhp(and this looks better the RS4 injectors,but those have spray pattern issues which the RS3 injectors may not have...ask Rick on that one).

Mine was adequately fuelled at 500bhp(i.e. no signs of lean running etc) with RS4 injectors,an Autotech HPFP and uprated LPFP system.

The TT-RS or RS3 LPFP can be used,but needs proper setup of the PWM controller to use on the S3.

Above 500bhp fuelling is a serious issue,and needs careful attentionand running a sequential,progressive 8 injector system is one solution,but complex and costly.
That wouldn't be needed here.

We just went in a totally different direction with mine(as above) and that showed no signs of flow limiting even well into the 600s,with USP Motorsport's auxiliary LPFP pump system.

 

[HHS3]

There's several factors to consider.

Firstly,it IS possible to increase flow through an injector by increasing the fuel pressure across it,up to a limit.

However,the other limiting factors are:

1.LPFP flow capactity....on a stock S3 this is around 440bhp or thereabouts.
2.HPFP flow capacity....an uprated HPFP will still have a flow limit,but I can't recall offhand.
3.Raising the FPRV pressure may also increase the load on the cam follower and pump internals.

Rick states above that RS3 injectors are good for around 600bhp(and this looks better the RS4 injectors,but those have spray pattern issues which the RS3 injectors may not have...ask Rick on that one).

Mine was adequately fuelled at 500bhp(i.e. no signs of lean running etc) with RS4 injectors,an Autotech HPFP and uprated LPFP system.

The TT-RS or RS3 LPFP can be used,but needs proper setup of the PWM controller to use on the S3.

Above 500bhp fuelling is a serious issue,and needs careful attentionand running a sequential,progressive 8 injector system is one solution,but complex and costly.
That wouldn't be needed here.

We just went in a totally different direction with mine(as above) and that showed no signs of flow limiting even well into the 600s,with USP Motorsport's auxiliary LPFP pump system.

Nice one, thanks for explaining. Even though I'm not the most knowledgeable on engines I still find the mechanics of it all very interesting!

Once you have the custom BCS exhaust on and DQ500 (can't wait for these!) then your beast should comfortably run run over 600bhp IIRC from your previous dyno run at Storm, so will you then be looking to upgrade your RS4 injectors as they top out around 600bhp?

 

[S3Alex]

Nice one, thanks for explaining. Even though I'm not the most knowledgeable on engines I still find the mechanics of it all very interesting!

Once you have the custom BCS exhaust on and DQ500 (can't wait for these!) then your beast should comfortably run run over 600bhp IIRC from your previous dyno run at Storm, so will you then be looking to upgrade your RS4 injectors as they top out around 600bhp?

No probs...I find all of it very interesting,and whilst I grasp the basics,and some of the physics,the really clever bits are beyond my understanding.

Without wanting to divert this thread,mine can already run over 600bhp(as it did on setup,with the Syvecs ECU running 2.1bar),but the old exhaust was restricting flow,so it has to go.
It runs a set of S3 direct injectors up to around 360bhp,and brings in a set of port injectors(from the old S3) progressively above that,run from a separate LP fuel rail.

 

[HHS3]

No probs...I find all of it very interesting,and whilst I grasp the basics,and some of the physics,the really clever bits are beyond my understanding.

Without wanting to divert this thread,mine can already run over 600bhp(as it did on setup,with the Syvecs ECU running 2.1bar),but the old exhaust was restricting flow,so it has to go.
It runs a set of S3 direct injectors up to around 360bhp,and brings in a set of port injectors(from the old S3) progressively above that,run from a separate LP fuel rail.

Woops forgot I was on the wrong build thread, sorry cupraraj!

Ah I see that makes sense as I was getting confused thinking that you were still running the RS4 injectors. That's some pretty impressive engineering I must say, looking forward to see what it can produce after the next round of upgrades!

Right, I'll hush up now.

 

[S3Alex]

Woops forgot I was on the wrong build thread, sorry cupraraj!

Ah I see that makes sense as I was getting confused thinking that you were still running the RS4 injectors. That's some pretty impressive engineering I must say, looking forward to see what it can produce after the next round of upgrades!

Right, I'll hush up now.

Trot on over to my thread and I'll run through it there if you want.