I have a 2001 Kia sportage and it chugs when changing gears and the check engine light flashes only while it is chugging but the light is always on I have a obd2 code scanner but when I run the codes it tells me theres an error and won't give me any codes any ideas???? I've changed spark plugs/coil packs/wires/egr/valve mass air sensor/throttle positioning sensor/cam positioning sensor and cleaned the connections on the harness that the coils plug into HELP!!!!!!!!!

It's a manual trans but anyways I finally took it to the shop and for 250 bucks the problem was solved the mechanic told me it was a combination of things but it was mainly bad coils and fouled injectors apparently you can can buy faulty parts but whatever problem solved thanks for your input I appreciate it It's a manual trans but anyways I finally took it to the shop and for 250 bucks the problem was solved the mechanic told me it was a combination of things but it was mainly bad coils and fouled injectors apparently you can can buy faulty parts but whatever problem solved thanks for your input I appreciate it