2006 dodge caravan 3.3l v6 with 126k kilometers here. I’ve put a new battery, alternator, starter, spark plugs and wires, so none of those can be the problem. I can start the van up and it idles ok for a few minutes, and even drives, but not for long. Firstly, even when just idling after just starting it up, there is a gas smell outside the van. Then, after a few minutes, it starts smoking white smoke under the hood, probably from the exhaust manifold which gets extremely hot even after less than a minute, probably because of how badly rusted it is. Not sure if it is overheating because I haven’t been able to keep it running for long enough to see if the temp gauge goes up. Also, when I put it into any gear other than park, it starts shaking significantly and seems to almost stall out, and sometimes does. The engine sounds weak, and I also have significantly decreased power as sometimes I can’t even drive it up ramps even if I’m flooring it, it just revs and drives halfway up the ramps but won’t make it up (I can drive it up if I try immediately after starting it, it only loses power after a few minutes). The previous owner also said it had poor gas mileage when it was still drivable. It’s worth mentioning that the van had been sitting for 2 years before I started working on it. I feel like it is fuel system related, such as the fuel injectors, fuel pump, egr valve, etc. but I’m not sure and don’t want to just start guessing what to replace since all these are expensive, so I’m trying to exact cause of this.