But, then, I've been running my ZS since I bought the car new with it - & it never a problem! Moved to Kansas & 'thought' I needed a manual choke for the winters there - biggest mistake I ever made with that car & I went back to the auto choke within a short time...darned manual choke never would work right! But, I kept all my emissions controls in place - don't know if that affects the manual choke or not but I threw it as far as I could when I removed it.