Deceleration Fuel Shut-Off Check
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 1987 Volkswagen Scirocco, 1987 Volkswagen Quantum, 1987 Volkswagen Jetta, 1987 Volkswagen Golf, and 1987 Volkswagen GTI. However, it is still accessible from the selected car via links, so may be relevant.
- Engine oil temperature must be at minimum of 120°F (50°C). Reconnect wiring to temperature sensor. Start engine and run it at 2000 RPM briefly. Release throttle.
- Differential pressure regulator current reading should briefly be negative (-30 to -60 mA) and return to positive when engine reaches approximately 1300 RPM. If not, check for open idle switch signal at ECU connector terminals No. 2 and 13. If switch is good, replace ECU.