1,9 tdi bkc tuning question


Golf mk5 1,9tdi
Golf 5 1.9tdi 104hk bkc engine with turbo gtb1646vc and map sensor from 2l, injectors from 2.5tdi bnz.

Everything is mapped but not the injectors, and im getting the fault code underboost, is that related to the injectors not mapped inn?

those were the injectors i was recommended, should i change them back to the original injectors or map these in for better improvement and hk?"

Im having an hard time finding anyone willing to tune in the injectors, so i think i have been fooled by the guy recommending these injectors because i’ve heard it has a different spray pattern than the original ones? So im also wondering if it makes a big difference if the spray pattern is different than the original one.

Hoping for some good answers and sorry for bad english

Regards Andy
Underboost is not related to the injectors, it could be the turbo actuator not setup properly or the air flow metering not properly registering.

The map needs adjustment if you change the turbo, injectors or air flow sensor otherwise your ECU will protect itself from the strange readings it's getting and go to a limp home mode.

Without seeing the car it is hard to diagnose, it will be easier if it can be mapped on a rolling road.

The injector pattern will change the way the fuel burns but should mean more power and a cleaner burn as long as the fuel pump has enough pressure to feed them.
Okok, because i didnt have any fault codes before i changed the injectors and im having troubles finding anyone here in norway that can do this job. I did extract the file out of the ecu myself, so i can find someone online willing to do it. But the file size seems wierd. Its only 1048mb or something? I tought they were atleast 2096mb?‍ do you know any good tuners that could take a look at it? For payment ofc. Last time when i tuned it i took it to a tuning company, they had to take the ecu out, and i find that very strange, because i extracted it straight out with a kess v2 master tool i bought on ebay and im 100% that this is some cheap china product aswell
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If before to change injector all was good and every sensor/ actuator is now scaled good, try to check vacuum pipe, also a little leak can do this issue

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