For cold start problem check coolant temp sensor, bosch connector to it and wire terminals under rubber boot and terminal pins to be sure they are locked into connector. Pack sensor terminal end with dielectric grease. the 164 engine will start fine hot but not cold if sensor connection bad. It is the "choke" device. See item 4 in picture it sets under top hose to thermostat at a 45 degree angle.
For sticking throttle at 2k check min/max switch (item 8 second pix) on throttle body for sticking and proper clicking 1 to 0 and 0 to 1 degrees.
For sticking throttle at 2k check min/max switch (item 8 second pix) on throttle body for sticking and proper clicking 1 to 0 and 0 to 1 degrees.