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

[ub7rm]

Good point on the VW not letting anyone copy their map bit.  I kindov imagined that remaps work a bit like an extension or an 'overlay' to the 'stock' map that filters certain commands and modifies them according to a set delta or even range of deltas and letting the stock look up tables provide the absolute value to modify. 

I may be speaking utter utter shyte - wouldn't be the first time 

[illyun]

I'm still not convinced by the above in terms of the car over-fuelling/running rich... this is because the car in stock mode should not run rich full stop.  Duncan, have you been to VW and had your car ECU completely rewritten rather than just updated?  I would have thought that this would cure the problem if it is an ECU issue programming issue.  Then it would be safe to put the MRC map back on without the (imho, questionable) workarounds for excess fuelling at higher rpms.  If it was my car, I'd want to know why my car isn't behaving like other GTIs...

[duncan]

I'm still not convinced by the above in terms of the car over-fuelling/running rich... this is because the car in stock mode should not run rich full stop.  Duncan, have you been to VW and had your car ECU completely rewritten rather than just updated?  I would have thought that this would cure the problem if it is an ECU issue programming issue.  Then it would be safe to put the MRC map back on without the (imho, questionable) workarounds for excess fuelling at higher rpms.  If it was my car, I'd want to know why my car isn't behaving like other GTIs...

i know what you mean, and i do want to know - but have spent 80% of the time ive owned the car trying to figure out why things arnt as they should be... and since the car is underwarranty for another year im happy to leave it now since its not something complely obvious im happy to just enjoy the car for now.

i do belive that it could be down to this wald convesion being crap and leaving incorrect tables on the ECU.

at the end of the day it appears to me that somewhere down the line the ECU has been badly programmed but the only obvious problem was the rich ness at high revs, once this was overwritten it could be and not saying definitley is the possible end to my problems invovling running rich

[ub7rm]

I'm still not convinced by the above in terms of the car over-fuelling/running rich... this is because the car in stock mode should not run rich full stop.

I agree..... in this country.  But if its an ECU set up for a different country, where environmental conditions not seen here are present that the ECU has been programmed to compensate for - its a possibility.  In that country, running on that countrys fuel no overfueling may be apparant.  One cars meat is another cars poison after all.....

Also remember that its not  sensors or instumentation showing the car to be overfuelling, its the tuner who is presumably comparing it with his experience....of UK / European cars.

Another thing to bear in mind is that when that ECU is plugged into the VW diagnostic machine, it will match up the map that should be on it with the region its supposed to be in.  Not the region its actually in unless you ask specifically for that to happen.

[Steve Baker]

The easiest way to discount an ECU fault would be to substitute the ECU with known good from another vehicle and data log accordingly. If the excess fuel situation still exists then there is clearly a fundamental underlying problem that really needs sorting before altering the map? 

[duncan]

The easiest way to discount an ECU fault would be to substitute the ECU with known good from another vehicle and data log accordingly. If the excess fuel situation still exists then there is clearly a fundamental underlying problem that really needs sorting before altering the map? 

agreed!!!

and would have liked to have done that, but the having an ECU to swap would be the first mission, then the labour charge for swapping and diagnostics would cost me at least a few hundred and since the car is still under warranty am pretty reluctant to spend money on it.

getting the remap made sense in a way although it didnt diagnose the full problem, it was at least 2 hours of free diagnostics that ruled out alot of problems that the car could have had which in turn made the remap much cheaper since i got all that labor for free!

also the way i see it if this could be the start of a problem that would need fixing it would become obvious enough for VW to fix the car under warranty

[Phil Mcavity]

Rolling road day coming up Duncan, bring it down mate and have a look.
http://www.mk5golfgti.co.uk/forum/index.php?topic=2883.0

[duncan]

Rooling road day coming up Duncan, bring it down mate and have a look.
http://www.mk5golfgti.co.uk/forum/index.php?topic=2883.0

looks good - not a million miles away from portsmouth. just need to check if im working that weekend, got a feeling im off so would be good to make it down there.

although I almost dont want to put the car on the rollers becuase if its still only putting out 220bhp ill be so pissed off lol

[Phil Mcavity]

add your name to the thread list if you can make it Duncan ok.

[duncan]

add your name to the thread list if you can make it Duncan ok.

will do - should know by tuesday