The most common reason a vehicle jerks when accelerating is a misfire. Checking for trouble codes can make the diagnosis a lot easier.
Your Altima’s engine is a pump. It mixes air and fuel and needs a strong ignition of the two to run correctly. If any of these three variables are off, you will not have optimal combustion, and it can jerk while accelerating.
Start with the check engine light.
If your check engine light is on, the first thing that you should do is scan the computer system and see if there are any OBDII diagnostic trouble codes. You can pick up a scanner pretty cheap. Or, most major parts stores will provide this service to you free of charge.
Here are the most common issues that cause your Altima to jerk when accelerating:
A few things can cause an engine to misfire. More often than not, it’s going to be the spark plugs or coil packs that are the culprit. A misfire is the most common reason your Nissan Altima jerks while accelerating.
Here are some common misfire causes.
While the ignition system is the most likely reason a vehicle will jerk when accelerating, it is not the only one.
Your Nissan Altima’s exhaust system has three functions. It releases exhaust gasses behind the car, scrubs pollutants via the catalytic converter, and helps the engine adjust the air/fuel mixture via O2 sensors. All three can cause your Altima to jerk while accelerating.
Your Altima’s exhaust must pass through the catalytic converter to get to the tailpipe. It is possible for the converter to clog. This is particularly true if a rich air/fuel mixture has run through it for a while. When it is blocked, your Altima will struggle and jerk when accelerating.
You may also notice that it has a “top speed” much lower than you would need to drive on the highway. This happens when the catalytic converter is almost full and the engine is choking on its exhaust.
The oxygen sensors meter the exhaust as it exits the combustion chamber. If one is faulty, it can change the air-fuel ratio to the point that your Altima starts jerking.
Have you driven your car over something that scraped the bottom hard? Your Altima’s exhaust pipe may have gotten pinched. When pinched, exhaust gasses can’t escape, and you’ll feel a jerking sensation (or a lack of power).
Modern vehicles use crank and cam sensors to fire the spark plugs at the perfect time. There are two ways that your Nissan Altima’s engine can be out of time. A crank or cam sensor is having an issue, or the timing chain has jumped a tooth.
You should hear slapping under the timing cover if the timing chain has jumped a tooth. If a crank or cam sensor is not reading the timing position correctly, it can cause your Altima to jerk.
Here’s how to replace the crank sensor on an older Altima, which is a very common reason they jerk when accelerating.
Your Altima needs fuel to run. If one of your fuel injectors is clogged or not firing correctly, it can cause a jerking sensation.
Outside of bad fuel injectors, a bad fuel pump or fuel filter can also cause a jerk while accelerating. When either of these goes bad, there is insufficient fuel pressure at the fuel rails. The best way to determine if there’s a lack of fuel is to test the fuel pressure at the rails.
You should check if the air intake is blocked with something foreign. Or if you have a filthy air filter. Not enough air will also throw off the air-fuel ratio and make the Altima jerk.
Checking your air filter only takes a second.
The motor and transmission mounts connect your Altima’s engine and transmission to the chassis. If one breaks, it can lead to jerking when braking, accelerating or putting the vehicle in gear.
Good luck figuring out what is causing your Nissan Altima to jerk while accelerating. Everything described above should cause the check engine light to come on, with the exception of a bad motor/transmission mount. So, make sure you get the trouble codes and take it from there.