This is a detailed video showing how to test and clean a Bosch cold start injector or cold start valve. At the end of the video we cut open a Bosch cold start injector injectors to see exactly how it works and speculate as to why this one might have failed. A faulty cold start injector can lead to:
1. Hard start or no start
2. Rough idle
3. Starting then stalling
4. Excessively rich mixture
5. Back firing and smoke
6. Poor running at low speeds