I recently acquired a 318i 2dr hatch M43 engine and the car's exhaust fumes suggest unburned gasoline. So I install new sparkplugs and replaced all the vacuum hoses and the car's idling was smooth as silk but as I drive the car i notice the idling becomes a bit erratic and then slow rpm hunting kicks in. The previous owner replaced the MAF sensor and installed a 2nd hand MAF sensor and I believe it is still defective. I also noticed that when I turn on the ignition I do not see any symbol of the injector. (the car i believe is an OBDi and the check engine sign is not yet present). Is the ignition coil pack and the MAF sensor defective? If the coil pack is defective will it show in the diagnostic scanner? Thanks so much in advance.