been trying to find out why my 1999 td5 overfuels all the time ,ifind i feather the throttle on acceleration as it is a bit embarrasing.
i removed the ecu msb101170 and looked at the chip inside which is a atmel at27c1024 ,when i search this it says it is a eprom does this mean it has been remapped and not a very good one.any advice welcome as this is doing my head in

Sounds like either a turbo which is not boosting properly due to a stuck open wastegate

"OR"

A ****e remap with a generic mapping causing the overfuelling.

You need to speak to someone like Gary at Alive Tuning as he tailors every map to the engine and the driver depending on what you want. He could also put your ECU back to standard mapping if that is what is wrong.

All the chips are EEPROM, if that chip is soldered into the circuit and looks like it was there from the beginning it means it's not remapped, usually those who are remapping the MSB ECUs are removing the chip and solder other chip with socket to be easyly replaceable

plug in a tester for that black smoke first, it can be a faulty MAF or AAP sensor too