Bosch 02 Sensor - Mk1 w/ lamda - Single Wire
With a fresh 02 sensor you will be assured of not only the best performance at wide open throttle, but also of the best MPG and cleanest emissions. Easy single wire connection (non-heated).
The CIS fuel system is a great set up for naturally aspirated motors, and when everything is up to spec, it is dead reliable and excellent for performance. The problem is when vacuum leaks and faulty fueling parts are not replaced it will quickly have problems, leading to hard starts, inconsistent performance and unreliable running. Keep your early car original, and reliable, with quality new fuel parts. Most are from Bosch or are OEM VW.