The injectors or spark plugs might be firing wrong. You should get it checked out as soon as possible.
Probably in need of a good tune up.
Probably in need of a complete tune up.
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.
Because it is a ford, buy a Chevy
Try checking your spark plugs & wires. Can also be caused by dirty fuel filter.
The overdrive allows the engine to run at a lower RPM on the highway It saves gas , the transmission will run cooler etc.
Car will run rough ,backfire and you may be able to here it rattling.
yes i could make it run rough. not getting the right air fuel mixture will cause a car to run badly.also check the timing to see if it is off.may need to replace timing belt or chain and gears.
Your vehicle has an overdrive button on the shifter maybe. When you start your vehicle, overdrive is always on. When you tow something, you want the overdrive to be off, otherwise the transmission will run hot and that will lead to bigger problems.
Corrosion inside the distributor cap. Get a new cap and rotor.
A large vacuum leak. Check the gasket under the throttle body for leaks.
If you have replaced plugs and wire most likely one of your coil pack usually run about $50