Hi guys,
I recently installed a used TPI system on my 86 IROC. It has been running great except for extended cranking time when it is cold. After some research i found out that the Coolant sensor is usually the culprit. Today, i found that the ground wire from the sensor was cut. I resoldiered the wire to ground "fixing" the problem. Now the car starts readily but sets an error 15 "CST low temp indicated". I measured the voltage of the sensor wire unhooked from the sensor and have 5V. The sensor measures 450 ohms which is perfect. The 5V drops to 2.5V with the sensor connected. I pulled the ECM fuse for 30 seconds to clear it with no luck. HELP!!!!