The 1.7 uses a thermo switch only, not a thermo-time switch. If it fails causing a short to ground it would cause the cold start valve to operate regardless of the engine's temperature, but this would only occur while the starter was engaged. The most common failure mode, however, is that it is open and will not supply ground to the cold start valve even when cooled to 30 below zero. If your cold start valve is the culprit causing an overly rich situation it is most likely because the cold start valve itself is leaking........(test it by removing the valve while it is still connected to the fuel loop and pressurize the system. If it is even just wet on the end it is a leaker) You can reinstall it and remove and plug the fuel line to it untill you replace it........if you think you really need one.....While I was busy taking the long way to say it, Jeff said just about the same thing in the above post