I recently purchased a 2001 Nissan Altima from a friend, and the car was sitting up at their house for over a year. Grass was growing heavily around it and there were even ants and wasps nests in knooks and crannies throughout the car. Prior to buying the car, I was told that the car would stall at stop lights, but would turn back on. They thought it was the catalytic converter. I am aware that the emissions aren’t coming out of the muffler, thus creating a loud noise when driving, but I am not sure that is the core issue. We did discover that the alternator was on its last leg, so we got that replaced. The battery is 4 years old as well, plan on replacing it soon. Here’s my experience:
The car will occasionally stall at stop lights, unless I put the car in park and rev the RPMs a little. Lately, it has also been stalling at low speeds or when I have to come to a hard stop. A couple times now the car has stalled on me while slowing down to turn onto a street. Before we got the alternator replaced, the car would not turn back on. The car will turn back on now, but as of lately it has been struggling. The RPMs will drop back down to zero after turning the car back on and die again, creating some stressful situations when it dies on me in traffic.
The car will also thrust forward when I’m going at speeds above 50mph, and more so when the AC is on. I’ve even noticed that when this occurs, even with my foot on the gas accelerating, the mph will slowly drop.
Any clues to what the issue(s) could be? I’ve considered the fuel pump/fuel injectors, or a mass air flow sensor or O2 sensor, catalytic converter? I’m not sure. Please help! It seems like the car is having more trouble starting up after it stalls than it did before.