Reasons why car shuts down while slowing down
Are you in dilemma of what is wrong with your car because your car works well when you are at high or steady speeds but as soon as you attempt to approach a stop, the engine switches off.
Listed below are causes of the condition:
Dirty/faulty throttle body - carb cleaner can be used to remove dirts or carbon. If the throttle body is faulty, it should be replaced.
Faulty idle stabilization valve or wrong idle adjustment setting - for cars that have manual idle adjustment screw, this can be adjusted to correct idle engine speed.
Dirty/Faulty MAF - Mass Air Flow sensor can be cleaned with Mass Air Flow sensor cleaner. A faulty MAF sensor should be replaced.
Dirty/Blocked air filter - A very dirty or blocked engine intake air filter can starve the engine of air, especially at low engine speeds. It will also limit power as it won't let enough air reach the engine at high engine revolutions.
Wrong engine timing - when there is nl proper correlation between the crankshaft and camshaft, the engine might be going off at times.
Faulty Crankshaft position sensor - When this is the cause of engine shut down, the sensor should be replaced. Unfortunately, sometimes, it does show any fault code when it causes this fault.
Other sensors - sensors like Oxygen/AF sensors, camshaft position sensor can cause engine shut down too.
Large vacuum leak - The effect of vacuum leaks are minimal at higher engine revolutions especially when the leak is not large. A large leak can cause engine shut down.
Faulty transmission lockup system - As the vehicle speed reduces, the lockup clutch is suppose to disengage. If there is any problem that makes it not to disengage, it can make the engine to stall at it approach a stop.
Fuel pressure issues - Fuel delivery issues can also cause similar symptoms