you most likely need an alignment or your tires just need to be balanced
The vacuum lines for a 2000 Cavalier are located all over the engine bay and under the dash. A break in any line can cause rough running.
Inside the lower part of the engine. The pistons are connected to the crankshaft by way of rods. Here is a rough diagram.
There can be several things that will cause your 2003 Chevy Malibu to run rough and not shift into fourth here. The probable cause is a lack of fuel. Due to a bad fuel injector.
The motor mounts hold the engine in place, but to not cause shifting issues. The rough shifting is caused within the transmission system, either electrical, vacuum related, or inside of the transmission.
I have a 1997 cavalier. If it is the same and I think they are. The best thing to do is go to Wal-mart and get the installation kit. Inside the kit are directions on how to get the old stereo out. Because you have to take the dash off to get to some of the screws. It sounds rough but really it is easy.
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There is no air in line Fuel pump pressursizes line and air automatically bleeds from the injector Not enough fuel or pressure will cause rough start
The Chevy 4.3 egr system is important to the proper operation of the engine. A clogged egr can cause rough idle or low fuel economy, among other things.
timing off
check the spark plug wiring order
There are many things that can cause a rough idle on this car. The computer could be going out, the engine may not have enough oil, and the engine may not be getting enough fuel or electricity.
could be the o2 sensor but most likely sounds like the spark plugs or wires look up misfiring on google