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1.4 TSI Twincharger (160) Stage 1 / 2

Mk R

New member
Hi again,

Sorry if this is thread jacking but i thought i'd share the responses from eTuners and TMG who both took the time to provide a more thoughtful technical response.

eTuners would be a custom dyno map by their rep here in Sydney for the car which can adjust knock sensor sensitivity settings and AFR. These can be set based on customer requests or left to the tuner to map out based on their understanding of the setup and safe parameters.

TMG can do the tune over in Greece by sending an ECU to them with the car's spec. Obviously driving from Sydney or London to Athens is inconvenient. From TMG:

The best thing is to send us the ECU and we ll send back to you.

According to Remap, when you build a new file, you adjust all filters, including knock sensors. The threshold of filtering them in a way that the car works safely is vital. We've made thousands of tests and we know exactly the threshold between power and reliability. So each filter is adjusted in respect with engine reliability.

The AFR is set to be in stage 2 around 0.77-0.8 to revlimit.
We adjust the maps in order to protect the engine, so of course we do not remove the component protection maps.
 

The_Hawk

New member
It's been a few years since I was last in this thread, but it's been a great read of later information and I thought it was worth posting up some of my experiences.


Contrary to my post above - i have been getting issues after i fitted the DV+.

Same day i fitted it i had a misfire EML on a hard 2nd gear WOT pull. I put it down to the sparks which i have been experimenting with the last few days (more on that later).

So i put the BKR7EIX back in, gapped them to 0.65-0.7mm and thought all was good.

However day later i had another misfire EML on hard 3rd gear pull.....its on random cylinders - first 1 &3 and now 2. So its nothing specific to a particular cylinder.

I have noticed the misfire occurs if i go WOT after not long starting the car up (say a few minutes of driving) - but it is up to coolant temperature from a previous non WOT run. It doesn't do it after a good bit of driving or if i give it a run but not WOT at first and then start doing some tearing around with full throttle.

Prior to the DV+ install i had no misfires.
I have a theory on why the DV+ appears to be causing misfires:

The DV+, with their piston spring to regulate boost pressure is putting more boost in momentarily when doing full throttle than is expected by the ECU map. This exactly how it improves throttle response, by not venting all the boost pressure when you go off a throttle or in this case kickdown gear change down when i stamp my foot to the floor.



GFB DV+ boost chart shows this is what happens when you do a full throttle request, for 0.5 seconds it ends up providing more boost than you would have with the factory DV. Now the ECU is only putting in X amount of fuel during this period - so for this time it will run leaner. This is why some people with the DV+ have had system too lean soft codes.

So i'm at full WOT, max boost request and the engine is running momentarily leaner for a short period - and bang i get misfires right when this happens, i.e. the 0.5 seconds after a kick down gear change. With a DSG, a gear down shift is a momentary release of throttle (close throttle body plate) and then reopen...and also a open DV valve at same time. Ecu is expecting a boost pressure drop and is simply not getting it due to the DV+ gradual boost release mechanism.

These engines at the best of times are close to misfiring - which is simply down to having high boost pressures at WOT, on sparks that are likely to carbon foul due to low cylinder temperatures during normal driving, with lean mixtures and of course stock gap sizes being a bit too big on the sparks.

Now add in a stage 1 (closer to stage 2 for the new APR map), pushing 23psi boost pressures, and a scenario where the electrode tip is not up to temperature and all it takes is a boost pressure spike on a lean mixture and hey presto - misfires!

For those that don't know the following conditions make it harder for a spark plug to fire - i.e. misfire:

-Higher air density (boost pressure)
-Increased gap size
-Lower electrode temperature
-Leaner air fuel mixture
-Higher humidity
-Lower discharge voltage (underrated or weak coil pack)

Forgot to mention it was also a bit wet, i.e. high humidity.
I have a scenario which meets most of those conditions when i am getting a misfire.

I have yet to pull the DV+ out to prove that it is that, and will do so shortly to prove the theory.

Long term solution should be to run the DV+ without the extra spring - making it operate like a OEM DV, but with ability to hold boost pressure better without leaking. Pity as will loose the throttle response gain - altho it was small.

Alternatively i am looking to get Audi R8 coilpacks at some point with an adapter plate for the 1.4TSI - they have a much higher discharge voltage which will alleviate all the above conditions causing a misfire.

The GFB DV+ definitely kicks out some errors because the DV+ reacts differently than a stock one and the computer gets confused. I'm told this is normal and it doesn't actually show any CEL on the dash, only in VCDS. I didn't notice any additional misfires, but more on that in a moment.


Yes, the APR map for 1.4 TSI's (twincharged) can have issues with some engines. Many of the greek tuners have had similar issues with APR maps where the 1.4 TSI is far more prevalent in greece.

Two problems arise - random misfires across all cylinders under maximum load around 4000rpm and intermittent boost limp mode.

The misfires seem to occur from overfueling with lambda as low as 0.7 and AFR 10.3. Engines with the newer revision injectors (used in most, but not all, mid 2010 engines onwards) have a wider spray pattern which can foul the sparks under heavy fueling - causing misfires.

The boost limp is where the engine suddenly drops back to stock boost levels and stays there for a while, with requested boost only being stock. It seems stem from actual boost consistently exceeding requested boost (lack of N75 control with it stuck at 100% duty for too long). Although it could be caused by something else, possibly false engine knock detection.

Anyway i got that map taken off, they did try to give me a tamer map but that was even worse and would boost limp almost immediately on a WOT. It is possible i have some other engine issues that don't show up on stock, but i can't find any from the logs and compression is good, i know ignition and the fueling system is good....if there is an internal issue such as poor valve sealing then it will all be resolved when i do all the head work.

I noticed the issues with the engine dropping back to stock boost levels, although only when the traction control / stability control activated. For example, driving through a little too hot and activating the traction control at WOT would drop boost to get traction, but then boost wouldn't return to tuned level. Cycling the throttle off/on would put it back to where it should be. Noting that I am driving a manual so changing gears naturally cycles the throttle more than you would with a DSG which likely means the problem is far less pronounced for me.

As I noted earlier in this thread I've updated the code to allow a two stage ESP/ESC button found in R spec models so you can turn that off completely should you feel the need.
http://www.vwwatercooled.com.au/forums/f20/apr-tuned-vehicles-question-you-81247.html

If I have ECS turned off, there are zero drops in boost the trade off being you have to be able to drive without ECS, not something I would recommend for most people as an everyday thing, but great on a track.

Haven't seen any updates here in a while. I hope all is well.

I ended up changing the transmission mount and also replaced the pendulum mount and my vibration issues disappeared.

I have also since installed an autopolar fis+ and began measuring different things. I did not realize this car records misfires for the car's life! I was horrified to see these figures on each cylinder. I do not and have never felt any of these misfires. The car has no error codes and no dash lights and feels normal while driving.



These misfires occur seemingly randomly and usually after lifting odd the throttle in 3,4 or 5th gear at low speeds. I am due to change spark plugs as part of regular maintenance but these figures surely have been occurring from factory considering that the car is 4.5 years old. Compression test shows 140 psi across all cylinders.

Would this be due to valve carbon deposits?


Ahh misfires. I'm guessing you dropped a piston on cylinder 4 at some stage given those numbers??

I've had a Polas FIS from the outset and have seen misfires across all cylinders with both stock and the APR Stage 1 tune. They were always pretty evenly distributed and never cause a light on the dash, and really unless I had VCDS hooked up or the Polar FIS+ I would never have known. Talking to other owners and this seems to be pretty standard for these engines...

I don't do a lot of KM's and mine operated flawlessly for 5.5 years and about 31,000km until it cracked a piston and lost compression on one of the cylinders causing a massive spike in misfires on the cylinder. That one set off a check engine light and I think running a tune and the Polar FIS helped identify the issue much more quickly than a stock motor. A rebuild later by VW (which was mostly only pistons) and it's been running nicely since, although I've only done about 7,000km in the three years since. Still getting a low level of misfires across cylinders.

If I was driving it more I would be more inclined to put more into it, the R8 coils and adaptors are high on the list to hopefully help with those misfires.
 

ROH ECHT

K04 PLAY
Hello, I have been searching and even posting my own threads for this but having no luck. Do you know it?

I am seeking the VW part number for the pressure limiting valve, or FPRV, on the fuel rail. Higher limiting valves for the mk5 gti are getting harder to find so I am looking into the 1.4L Twin-charge's FPRV. It is supposed to have a limit of 172.5 bar...page 26 here: http://www.volkspage.net/technik/ssp/ssp/SSP_359.pdf
 

The_Hawk

New member
Does this help, looks like it's #8


1596344867031.png
 

Ash2104

New member
Hello !
Greeting 🙏 hope all is well
Is the car still running mate ? It's been a very long time since your last post.
Did you manage to achieve what you were looking for in terms of performance with all the mods?
 
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