over boost at speed.

[tdi142]

Hi again guys. After having my pd 110 remapped too 142 i had problems with powerloss at full revs.The car went back and was mapped again and is fine now unless pushed at the top end which has come down since re mapping. I have just had a clutch conversion done to remove the dual mass flywheel and the guy who did the work (superbly should i say) Gave me an error code of 17965 from the diagnostics. I have told the performance centre about this but they say that it is the turbo.Surely if it was the turbo it would do this when revved out in every gear? I am no expert though . Has anybody encountered this problem before ? I am quite mechanically minded and do a mechanical job. If it is the turbo would you recommend that i strip and clean / replace myself?

[Yelloperil]

the powerloss you had before it went back - can you describe them?

did it feel like it was misfiring and kinda buking? - struggling for fuel? - only asking as mine does this but i'm not sure of the problem as i've only just bought it.

[ini]

The fault code indicates that you were 'overboosting', boost control - positive deviation.

This could stem from any of the normal vac leak, N75, sticky vnt issues, but is more likely to be from simply being remapped a bit aggressively on the top end (too much fuel/boost, or MAP not calibrated etc)

Extra fuel is added in higher gears/speed/load to allow for increased air resistance, so the problem will most likely not occur in lower gears.

It could be that the turbo needs cleaning, but i would try a simple, correctly attached 'boost valve' to alleviate the boost spike that may be the cause of your limp mode.

[tdi142]

No, sorry mate. The power loss is an instantaneous loss in torque and very little acceleration. It is like going up a hill in 5th gear. The management system resets when you swich off the ignition and turn it back on again and the cars power then returns to normal.

[FLENG2008]

sounds like you have the same problem like most on here, worn turbo vanes, unfortunatly you need to strip and clean the turbo....

i have had mine doing it for a year now, you just get used to flicking the ignigtion off then back on when on the motorway

[ini]

Yes, this is standard 'limp mode'/reduced power mode, caused by boost pressure higher than specified for a couple of seconds.

Most likely is the top end mapping, but could also be any of the normal causes.

[GTI MAD]

Hi TDI !
If i was going to remap the ecu of one of my cars i would'nt use anything but a "bluefin" type of device...
I believe this is the best option because you can always revert the ecu settings back to standard whenever you feel like it.
Would never recommend switching off the ignition however briefly, as you know you lose servo and power steering for a few instants,once in a while is ok but as a final solution its a no no!
I think you need to clean the turbo vanes as these are your culprit for the overboost fault and limp home mode..

[STEWY L]

i have no experience of it myself,but have read on our forum of similar
problems after remapping.
apparently the remap causes the boost pressure to exceed the "standard parameters" of the ecu,causing it to read overboost,and consequently putting it into "safe,or limp"mode.
however,according to one post i read,they said that it was possible to adjust those standard parameters in the ecu ever so slightly to allow the extra boost without dropping into limp mode.
can't vouch in anyway for authenticity,but worth a search?
regards,
stewy.

[malcolm1982]

Your car is fitted with what is called a variable geometry turbo, it is VERY common for the vanes to stick in it. This will cause the problems you describe.

[mwmackenzie]

sounds like you have the same problem like most on here, worn turbo vanes, unfortunatly you need to strip and clean the turbo....

i have had mine doing it for a year now, you just get used to flicking the ignigtion off then back on when on the motorway

Any info on how to clean the turbo?

Thanks

Mark