My 2002 Dodge Stratus shudders only for a few seconds when I start the car (sometimes). Any idea what this could be?
There may be a problem with the anti-drain back valve on the fuel pump assembly. What this valve does is prevents the fuel from draining back into the gas tank from the fuel rails and fuel line as the vehicle sits. If the fuel does drain back into the gas tank it leaves air in the fuel system. Then when the vehicle is started it takes a few seconds for the fuel pump to purge the air out of the fuel system and build the proper fuel pressure. This then causes the engine to shudder at start-up.
To verify if this is the problem, the next time you go to start the engine, turn the ignition switch to the run position so the dash lights come on for two seconds and then turn the ignition off. Repeat this three or four times and then try starting the engine. If the engine starts without a problem suspect the anti-drain back valve on the fuel pump assembly.