06 Buick Excelle 1.8 What are the causes of manual engine jitter?

There are many reasons for this engine's jitter.

First check whether the throttle valve is too dirty and whether the vacuum tube leaks. Then check whether the ignition of the spark plug is normal. Whether there is too much carbon deposit in the injector and whether there is leakage in the ignition coil. Whether the engine is short of cylinder, the cylinder pressure is insufficient, the exhaust pipe is blocked, the timing is jumping, and the engine electronic control system is faulty requires computer detection.

All these will cause the engine to shake, so we should test it according to the actual situation.

I hope I can help you. If there is something wrong with your car, ask the car mechanic. 4S shop professional technician, 10 minutes to solve.