nocrap 0 Posted January 5, 2010 Hi all... Thought some people might find this useful if they're having issues getting their 16v started. I've been looking at the purpose of sensors in K and KE-Jetronic systems and found some useful info here and there. one thing confused me though... The early valvers use a thermotime switch to control the 5th (cold start) injector but the later KE-Jet 9a engines dont use this sensor yet still have the cold start injector.... what controls the opening and closing of this in this system? Thermo-Time Switch If your car incorporates a cold-start injector, it will be controlled by a thermo-time switch. While you crank the engine-and if it is cold- the thermo-time switch will allow the cold-start injector to open. It operates much like the thermostat in your home, using two metals sandwiched together, each with a different rate of expansion from heat. A second, heating circuit in the switch begins to warm the bi-metallic switch as soon as you start cranking, so the switch will shut off before you flood the engine. The thermo-time switch works by grounding out the current to the cold start injector. If it fails to energize the cold-start injector, a bad switch can cause difficult starting (but not poor running). At the other extreme, if it doesn't shut off after startup and allows the injector to continue spraying fuel, mixture will be extremely rich. also found this useful page, if anyone cares http://www.covin.co.uk/tech_2.htm Quote Share this post Link to post Share on other sites
davidwort 0 Posted January 5, 2010 KE jet has an ECU that controls fuelling as well as ignition, you'll notice there's no warm up regulator or fuel lines to the WUR either as an electronic unit on the side of the metering head performs that function, the ECU must have a fixed time it triggers the cold start injector, or probably also related to the temp sensor/signal the ECU reads from on the head. Quote Share this post Link to post Share on other sites