for this problem, u need to re-tune your AFR. coz maybe your ratio not accurate. another thing, we actualy can set our fuel isometry from ECU. but most of workshop, if we said to tune injection... they just reset error code, set idling, timing and other parameters.
actualy u can adjust ur self. u just need skru driver (hehehe) do this step :
1) idle with no aircond, make sure rpm is 1 or 0.8(min)
2) on aircond and check your rpm. if they > 1 lets say 1.3, on your trottle body, got vacuum hose on it. have 3 skru. 1 of it printer 'A' try to tighten it a little and slow. and see again your timing. (kalau longgar, timing akan > biler on aircond. kalau ketat, timing akan < biler on aircond)
3) repeat 2nd step until your idle stable.
sebenarnya ader lagi satu cara nak tune. tapi kalau nak tulis dalam nie panjang. tapi cara dia macam nak setting carburetor motor/kereta. kene skru abis... kire braper pusing, pastu bukak kurang sket dari yg asal
p/s : kalau rpm < 0.7-8 sesetengah kereta akan bunyi macam pakai high cam. kejap naik kejap turun kejap naik kejap turun. tu kalau on aircond. sebab biler rpm idle > 1.2 /1.1 aircon akan on, biler on dia tarik rpm sampai 0.7 then auto aircond switch akan offkan aircond dan mende nie akan jadi loop.
okeh about this ting, actualy micro compressor just like another air source for ur engine. its connected to trottle body. just to give more air even trottle is close. u can tutup the hose and it not effect your engine. but if u open to much air, your engine can to lean and demage in combution camber. so conclution, u can tutup abit but don open it to wide. nak tulis susah... kalau aku cite berdepan ngan ko lagi senang.
sowi kalau ader mis information. betulkan kalau ader kesilapan ek.