Ok so went to R-tech today for Nick to work some magic.

The map I took the car in with was producing 195bhp / 240 lbft torque.

After about 45 mins the car was kicking out 248bhp / 298 lbft and it was producing the power easily, and behaving itself too.

Sadly this was short lived and not long after producing the above figures it started playing up again (exactly as it has been for the last couple of weeks).

Turns out it was Lean Throttle Cut that was kicking in, I had noticed in the logs that the throttle would be 100% open, but the ecu would start closing it and fluctuating it around 30 - 40%, hence the boost drop off, and then it would go mega rich.

Anyhow I took a few spares with me, and as I hadn't already replaced the front lambda sensor, Nick suggested we fit the new 1 I took with me, just to rule it out.

He jumped under the car to fit the new lambda sensor for me, and managed to melt his arse cheek to my exhaust .

Anyway the lambda sensor didn't cure the problem, but it did help with more consistant readings from the ecu, so I guess the old sensor was starting to get a bit tired.

Anyhow in the end Nick noticed that the fuel trims were starting to do silly things and would rise to 20%, at which point the ecu would pull the throttle shut.

So it suggested that the fuel pump is indeed playing up, but I have tried 2x stock VRS pumps and also 1 used Cupra R pump and nothing changed.

Nick then disconnected the evap line to the charcoal canister, and this improved things a little but it hasn't completely solved the issue.

For now the power has been capped at 245bhp / 297 lbft, I will fit a brand new cupra R fuel pump in the next couple of days, and keep an eye out for a good set of used cupra R injectors and then take it back for another session as Nick is confident there is more power to be had.

Awesome power nick = legend

Saw the pic lol that's a stinger lol

Awesome power nick = legend

Saw the pic lol that's a stinger lol

He did say it's the first skoda thats bitten his arse lol

Ah I'm with you know lol evap line.

Could lambda probe cause the boost issues ??

Nice

While you are waiting for the new pump slap a 4bar fpr, this will increase fuel flow 15% over 3bar fpr.

Ah I'm with you know lol evap line.

Could lambda probe cause the boost issues ??

Don't think the lambda will do much with the boost surge, unless the ecu decides you are going too lean, then it might do.

Nice

While you are waiting for the new pump slap a 4bar fpr, this will increase fuel flow 15% over 3bar fpr.

Already tried a 4bar fpr, it made no difference, but if the pump is going weak, it's going to struggle more if I stick a 4bar fpr on it.

I know that, please post back did a new fuel pump solved the problem and the part number of the pump!

I know that, please post back did a new fuel pump solved the problem and the part number of the pump!

Whilst I remember.

On the ETOS system, using a cupra R chassis number the fuel pump is listed as 4bar, for AUQ, AMK and BAM.

But using the VRS chassis number, the fuel pump comes up as 3bar and there is no other options avaliable.

Awesome power nick = legend

Saw the pic lol that's a stinger lol

are Nick's maps available in Kent? 248 bhp from a k03s? really?

wonder what magic he could work with a k04-001, let alone a hybrid!

are Nick's maps available in Kent? 248 bhp from a k03s? really?

wonder what magic he could work with a k04-001, let alone a hybrid!

There is more power in there he said, the boost is only 1.3bar peak at the moment too as he has capped the power for now.

are Nick's maps available in Kent? 248 bhp from a k03s? really?

wonder what magic he could work with a k04-001, let alone a hybrid!

Mine's running 225 wheel HP on a Shark Stage 2 map. Which is probably about 245 at the fly.

First three number/letters of the fuel pump part number defines is it Audi, Škoda, Seat or Das Auto. What I have found out is that the AUQ and BAM (LCR) are the same. So changing to lcr pump wont solve anything, also in my opinion AUQ 314cc injectors are too small for the horse power that you are currently running. I have similar problem with fuel starvation at high revs so I will try a combination of 4bar fpr and this;http://www.goapr.com/products/ms_fuel_pump.html

If I am mistaking please correct me....

Edited 6 March, 201313 yr by Gonzaga

First three number/letters of the fuel pump part number defines is it Audi, Škoda, Seat or Das Auto. What I have found out is that the AUQ and BAM (LCR) are the same. So changing to lcr pump wont solve anything, also in my opinion AUQ 314cc injectors are too small for the horse power that you are currently running. I have similar problem with fuel starvation at high revs so I will try a combination of 4bar fpr and this;http://www.goapr.com..._fuel_pump.html

If I am mistaking please correct me....

Ok as I said last night, when checked on the ETOS system, using my VRS chassis number, the fuel pump is listed as 3bar, there is no options for it.

Using a cupra R chassis number the fuel pump comes up as 4bar, and lists is as avaliable for AUQ,AMK,BAM.

Therefore it suggests that there could have been a fuel pump upgrade done on some AUQ models at some point, but my VRS wasn't 4bar from new.

Anyhow the part number for the 4bar fuel pump assembly from a cupra R is 8L0 919 051H, pierberg part no. 7.02700.00.0

Just to update this for anyone that's interested.

It seems my problem was the fpr starting to struggle and this in turn caused the standard fuel pumps to struggle too.

After fitting a brand new LCR fuel pump (4bar) and the 4bar fpr the ecu started removing fuel at 15% and the issue's went away.

I still think that your 3 bar fpr is OK, your pump started to struggle because you have raised the base fuel rail pressure from 3 bar to 4 bar. Stock fuel pump is rated according to pierburg 135 LPH@3bar but at 4bar has only 110LPH@4bar or even less than that.

Your peak boost is 1.4bar+your 4bar base pressure is 5.4bar which your stock pump must overcome to maintain constant base fuel rail pressure of 4 bar at all time. This is where the difference between lcr and vrs pump comes into play, lcr is rated 135lph@4bar and vrs is 135@3bar.

As rpms increase fuel injectors stay a longer period of time open which equals more fuel and stock pump runs out of breath at 5800rpm because it can`t hold cca 5bar of pressure where ECU demands the most fuel. Also with raised pressure stock injectors have 361cc@4bar .

Your multiplicative fuel trims are negative because your map is "written" for 314cc@3bar and in the low&mid revs you have surplus of fuel but fortunately our ECU can adapt fuel trims +-25% range. This comes in handy @5800rpm.

Edited 19 March, 201313 yr by Gonzaga

I still think that your 3 bar fpr is OK, your pump started to struggle because you have raised the base fuel rail pressure from 3 bar to 4 bar. Stock fuel pump is rated according to pierburg 135 LPH@3bar but at 4bar has only 110LPH@4bar or even less than that.

Your peak boost is 1.4bar+your 4bar base pressure is 5.4bar which your stock pump must overcome to maintain constant base fuel rail pressure of 4 bar at all time. This is where the difference between lcr and vrs pump comes into play, lcr is rated 135lph@4bar and vrs is 135@3bar.

As rpms increase fuel injectors stay a longer period of time open which equals more fuel and stock pump runs out of breath at 5800rpm because it can`t hold cca 5bar of pressure where ECU demands the most fuel. Also with raised pressure stock injectors have 361cc@4bar .

Your multiplicative fuel trims are negative because your map is "written" for 314cc@3bar and in the low&mid revs you have surplus of fuel but fortunately our ECU can adapt fuel trims +-25% range. This comes in handy @5800rpm.

Yes but the 4bar fuel pump still had issue's with the 3bar fpr, which is why I ordered the LCR injectors.

I only tested the 4bar fpr on the 4bar fuel pump just to see if it made any difference.

The lcr pump didn`t had a issue with 3bar fpr, injectors was the problem.

The higher the pressure in the fuel rail, higher is the flow through injectors,stock injector have 314@3bar and 361@4bar.

You can install a 10bar fuel pump, it will make no difference because FPR is the one who determine the base fuel pressure in the fuel rail.

The lcr pump didn`t had a issue with 3bar fpr, injectors was the problem.

The higher the pressure in the fuel rail, higher is the flow through injectors,stock injector have 314@3bar and 361@4bar.

You can install a 10bar fuel pump, it will make no difference because FPR is the one who determine the base fuel pressure in the fuel rail.

Yeh I totally see what your saying.

However the bit that makes me think there could still be fpr problem is because, the 4bar fpr gives approx. 15% more flow from the injectors right.

But now I have fitted the 4bar fpr, the issue has gone away, and the ecu is now going -15% on the fuel trim.

So that's making me think if the ecu is now wanting 15% less fuel, then the 3bar fpr "should" have been able to cope and the injectors would supply enough fuel.

OK I see what you saying but multiplicative trim is iirc for mid to high revs not only for high revs.

Stock inj+3bar fpr+lcr pump is good up to app 5500rpm and ECU corrects injection time to keep lambda at desired value ,usually I saw my fuel trim around +2% but in combination with 4bar fpr it subtracts 12-15% to compensate the surplus of fuel at mid revs.

This value goes from negative at mid revs to positive at high revs and ECU adjust injection time using information provided by lambda sensor. Let say @5800 map is requesting 12 afr but lambda is reporting 13afr, ECU will adjust afr by holding the injectors open for longer period of time, this way providing more fuel. And here is the catch, injectors can`t provide no more because they are to small and afr can`t meet desired value. What ECU does is to close the throttle.

You can`t see that in real time in block 032, this is learned value which ECU adjust over time.

I have just been and fitted the LCR injectors and refitted the 3bar fpr.

After 30 miles I can report the car is still behaving, so you are indeed correct, the fpr appears to be fine

After 30 miles the data in block 032 is at 0.0 and -17.2.

Interestingly after doing 100+ miles on track at the weekend and the 45 mile drive eachway the values were 0.4 and -17.8 with the stock injectors, 4bar fpr and LCR fuel pump lol.

hehe tnx for the info

You will see this value going up and doing all the time. Difference between this two setup is around 7%.

So long as it stays under 25% until I can get the mapped tweaked, i'm happy

Post back the dyno results, I am really interested in hp&Nm figures

Will do

Update:

Installed the cupra r pump, tested the pump in 100km and it seems that the problem is solved :sun: :sun:

Fuel trim are -0.9% & -10.8% which is expected.