disappointing performance continued....UPDATED after a day at MRC Tuning

[duncan]

well its been a long day and the saga continues....(start of my problems - http://www.mk5golfgti.co.uk/forum/index.php?topic=3310.0)

so too the car to tuningwerkes in croydon who were fantastic!! had booked the car in to get the DV changed and the front PCV swapped.

firstly we went for a test drive before the work began, Reuben who was looking after me took the car for a spin and did say that it was lacking in power, we drove for about 15/20mins,

the car then had the parts replaced, he took the car out again, then i took the car out and we both noticed a difference in performance, was more responsive, not by a crazy amount but then it was only slightly down on power so to be expected.

then he put the trial APR map on the car - i was knocked out - the car was rapid to say the least!! so much more response and pace through the gears. i decided i would use the trial map for a bit and come back to him in a week or so to get the full one put on.

on my way home i thought it would be interesting to see what the car is putting out now, just really to put my worrying to bed, once i could see the read out of what it should be producing that will 100% put my mind at rest.

here is where things get sh*t....

i took it down there, put it on the rollers and the car is only putting out 217bhp / 255lb/ft, speaking to reuben the lowest figures he has seen for an APR trial map is 245bhp / 289lb/ft.  the car also shows up to be running VERY VERY RICH.

i was very fortunate to have someone down there from MRC Tuning who had a ED30 running at 395bhp.  he offered to give me one of his maps if it was running full power once he put it on.

firstly he flashed the ECU back to standard which came up at 195bhp slightly under power but pretty close to what stock should be, then he put his map on.  i asked him what would be the min BHP i should be getting from his map - he stated 246bhp min and 285lb/ft min. you can guess the rest.... car came up wtih the same figures as the APR trial map.  so he ran VAGCOM on the car while it was on the rolling road to check the MAF and see why the ECU was requesting so much fuel... (the car also ran really really rich on his map too, he thought it ran rich on the APR map becuase it wasnt a very good map)

was very lucky to have him there as he really knew his stuff, and i got to take a look at an RS4 running 790bhp!!!!!!!!!!!

he thinks this could be done to 2 issues, the fuel pump is faulty which considering my car has only done 15k miles and driven very slowly (up to when i got it) would be unlikley. second thing he thought it might be was the lastest software version on my ECU, he thought that could be requesting too much fuel which in turn is making the car really rich arcross all three maps (stock, APR and his)

He works for a company called MRC Tuning - http://www.mrctuning.com/aboutus.php

so he invited me to come down to their office near Oxford.  He is going to spend more time looking at Data and if he cant get the map to 240bhp i dont have to pay anything, either way dont have to pay for diagnostic time which is a result...

after the rolling road session which consisted of 6 runs over a 45min period the car threw up an check engine light - which was diagnosed through VAGCOM as a wierd gear box problem which i was told was thrown up by the ABS, apparently the car gets confused when the front wheels are moving but the back ones arnt.

he doesnt have a rolling road there but does have a private road to do testing on so im sure it will be possible to tell if there are any problems

my questions:

1. anyone heard of MRC Tuning?
2. if it is a fuel pump, how can i get it replaced under warranty as its not throwing up any error codes?
3. is there any chance that this new software on the ECU (from VW) could be causing the problem?
4. if not the above then what else could cause the problem? he mentioned the fuel filter could need replacing
5. shoud i just pay for the map even though its not as high as it should be but is heaps better than standard?


sorry for all the questions - will probably ask even more when i think about it more

[vwrascal]

sounds like you are having the worst luck ever!!    good luck getting everything sorted   

[icenutter]

MRC tuning are well respected in the world of Audi S2 and B5 S4/RS4 tuning.

[john_o]

duncan thanks for keeping us informed  its a painful road but youll get there eventually.

You have at least ruled out PCV and DV now and its seems they helped 
From what you describe you still have a fundamental issue thats causing the rich fuelling in any mode (stock or mapped)
I cant see how a ECU map from VW would make any diff , as when flashed the APR or MRC maps would overwrite the code.
fuel filter is def worth changing as its cheap.
It would be preferable to log in stock map to find out why the rich mixture, but it sounds like he is willing to do the diagnosis so I may be inclined to let him 
Its getting to the bottom of the facts whilst not trying to change too many things at once.....
Surprised he would say APR isnt a good map if he knows VW/Audi tuning tbh
engine light always comes on when on the dyno , so yes no worries

[duncan]

duncan thanks for keeping us informed  its a painful road but youll get there eventually.

You have at least ruled out PCV and DV now and its seems they helped 
From what you describe you still have a fundamental issue thats causing the rich fuelling in any mode (stock or mapped)
I cant see how a ECU map from VW would make any diff , as when flashed the APR or MRC maps would overwrite the code.
fuel filter is def worth changing as its cheap.
It would be preferable to log in stock map to find out why the rich mixture, but it sounds like he is willing to do the diagnosis so I may be inclined to let him 
Its getting to the bottom of the facts whilst not trying to change too many things at once.....
Surprised he would say APR isnt a good map if he knows VW/Audi tuning tbh
engine light always comes on when on the dyno , so yes no worries

yea, he didnt say much that was bad about APR he just thought when it first went on the rollers all he could point too was a rogue map that was asking for too much fuel, he was data logging while it went on the rollers.

once it went back to stock ECU, it was still asking for too much fuel.

its strange that it wants more fuel and nothing is pointing to any particular component..

how likely is it that the fuel pump is faulty?

how easy would it be to get VW to change the pump under warranty?

[john_o]

unlikely to be the pump imho
more like some other factor is causing the ECU to request more fuel
maybe the o2 sensor has died?

[jonnyc]

well its been a long day and the saga continues....(start of my problems - http://www.mk5golfgti.co.uk/forum/index.php?topic=3310.0)

i was very fortunate to have someone down there from MRC Tuning who had a ED30 running at 395bhp.  he offered to give me one of his maps if it was running full power once he put it on.

Big turbo I presume?? 395hp is a pretty a 'optimistic' claim for a K04 car..

[QD MBE]

What did he say about the MAF?  May be worth plugging another one in, just to test.  I think a sensor is fooling the ECU into thinking it needs to fuel.  Is the Air filter ok?  Bear in  mind where the car was imported from, that sand gets everywhere...........

If i knew which sensor.......................  

This bit does seems strange, and does discount the MAF.  But I am not convinced.

firstly he flashed the ECU back to standard which came up at 195bhp slightly under power but pretty close to what stock should be

May be worth taking a look at the MAF.

[duncan]

well its been a long day and the saga continues....(start of my problems - http://www.mk5golfgti.co.uk/forum/index.php?topic=3310.0)

i was very fortunate to have someone down there from MRC Tuning who had a ED30 running at 395bhp.  he offered to give me one of his maps if it was running full power once he put it on.

Big turbo I presume?? 395hp is a pretty a 'optimistic' claim for a K04 car..

yep, i saw the car on the rollers and the print out - and that road is deemed to be pretty pessimistic in its results

[WhiteGTI]

What did he say about the MAF?  May be worth plugging another one in, just to test.  I think a sensor is fooling the ECU into thinking it needs to fuel.  Is the Air filter ok?  Bear in  mind where the car was imported from, that sand gets everywhere...........

I think theres been a mixup along the way with his documented engine code...because cars are LHD in the UAE, therefore meaning that his car can't have come from there  

[RunRabbit]

As above, a sensor is more than likely playing up or you have a boost leak. If it's over-fuelling across the rev range then it could well be a MAF or lambda sensor.

[duncan]

What did he say about the MAF?  May be worth plugging another one in, just to test.  I think a sensor is fooling the ECU into thinking it needs to fuel.  Is the Air filter ok?  Bear in  mind where the car was imported from, that sand gets everywhere...........

If i knew which sensor.......................  

This bit does seems strange, and does discount the MAF.  But I am not convinced.

firstly he flashed the ECU back to standard which came up at 195bhp slightly under power but pretty close to what stock should be

May be worth taking a look at the MAF.

when he was data logging the car on the rollers (stock map) he ruled out problems with the MAF, so did Reuben at Tuning werkes, but is still a possibility i guess.

also worth bearing in mind that the engine hasnt thrown up any codes what so ever (none found using VAGCOM)

[duncan]

As above, a sensor is more than likely playing up or you have a boost leak. If it's over-fuelling across the rev range then it could well be a MAF or lambda sensor.

it is only running super rich past 3500rpm to the limit

[autoperfection.com]

Sounds like a nightmare - hope you get it sorted

Jim 

[duncan]

do you think i should run the map if its still only putting out under 220bhp? the car feels fantastic with the map but obviously want it to work at full potential, you really notice the extra torque too!!

would be over the moon if this problem gets solved tomorrow but am not holding my breath....

also only one of the PCV's were changed - could it possibly be a faulty rear PCV as well? is it worth getting that changed as well?