I have a 2006 Pontiac torrent that has been occasionally having a very rough start. It sounds like an explosion in the engine and then after starting I typically hear a couple popping noises. Due to this I had changed out the spark plugs and wires, as I thought it might be a spark plug not firing as they were fairly rusted and looked original to the car that had 130,000 km on it. After changing over it seemed to be fine for a bit and running a lot smoother, but now I am having the same rough start and popping noises every now and then( I should mention that I have also cleaned out the MAF recently as well and replaced the air filter).It hasn’t activated a check engine light, so I am not sure if it’s just a fuel injection issue or not. If you guys have any ideas on it, I would be really grateful!