I have a Galant 2003 with a 2.0l 4G63 engine. Since I refueled my car, issues started to arise.
First the car gave sudden knock and the engine check light turned on. From then onward, the car's performance dropped to nothing, which was fixed by an engine tuneup reset and an inclusion of Soltron fuel treatment enzyme.
But after that, I have noticed that the car's cold start was not as it used to be. I have to start the car at least two times, as on the first cold start the RPMs drop and the car turns off.
I don't know if this is cause by the failure of the air flow sensor, the tuning or the battery or if it is an entirely another problem. What should I be looking for?