warning Lights

[Biggingertone]

Help... The emissions warning light came on last week and my car began to miss and judder so i took it to my mechanic and he plugged it into his code reader and a new mass airflow meter was diagnosed.

Left the garage and the warning light was out but the performance was the same so i took it back and he replaced it again but the problem remained but without a warning light.

I.m going back tonight and the warning light has returned so hoping that it shows something other than the MAF.

Anybody else got any ideas? Seems worse with the new MAF than before it was changed.

Thanks

Leon 2.0tdi ref sport 2008 56,000 miles

[Biggingertone]

Back from the garage and none the wiser.

Computer showed MAF fault code again but on the full diagnostic it showed it as working perfectly.

Car is still losing power and mis firing at low revs. turbo is working fine.
The mechanic says there is nothing more he can do and i should take it to a diesel specialist or the Seat main dealer both of which sound expensive.

I know my options are limited and i will probably have to do one of the above but as a non mechanical person i would like to go with as much information as i can.

Any help greatly appreciated.

Thanks