Engine cold electric start needle can not be opened

Symptom: The mechanic said: "A 125-type scooter (GY6 engine) is hard to start in cold condition and does not run smoothly for a few minutes after start-up, but the engine works well and starts easily. Cylinder sealing and compression is good; spark plug spark between the good; smooth flow of fuel; cleaning carburetor invalid; try for the ignition coil, ignition, ignition coil charge, pulse trigger coil is invalid; replace the engine oil, from the spark plug hole Note a small amount of oil in the cylinder, but also ineffective. Why can not find the cause of the malfunction. "Failure Analysis and Troubleshooting: According to the repairman to reflect the phenomenon of the car with the car carburetor set up a" electric automatic start enrichment device " Analysis of the characteristics of the car that the reason for the car is "cold when the motor electrothermal start enrichment device needle valve can not be opened, the combustible mixture can not be enriched, can not meet the needs of engine cold start. No other parts of the fault. The reason is that the engine works well and starts easily. Remove the carburetor inspection found that electric needle valve automatically start enrichment device due to stuck can not open. Eliminate the card lag, the engine cold start easy, idle work smoothly, accelerate the reaction sensitive, troubleshooting. It is noteworthy that the electric auto-start enrichment device power line open, then the engine cold start, work well, but the engine hot because of the mixture is too thick and poor work, difficult to start and start difficult.