- Is the spark plug dirty? Clean or replace it if its dirty. For your 150 cc Scooter we recommend a NGK C7HSA Spark Plug
- Make sure the carburetor and the intake manifold are tightly secured to the engine.
- Check the gasket between the carburetor and intake manifold. Sometimes the gasket is bad and caused leak. Solution: replace new gasket or just toss the bad gasket away and screw carburetor back. Try to start again.
