CIS-E Motronic
- Ensure ignition is off. Wrap a cloth around fuel distributor port near cold start valve. Slowly loosen distributor port near cold start valve to release fuel pressure. Connect fuel pressure gauge between fuel distributor port and end of fuel line to cold start valve. Disconnect differential pressure regulator harness connector.
- Start engine and let it run. System fuel pressure should 89-96 psi (6.3-6.7 kg/cm2 ). If system fuel pressure is lower than specification, perform fuel volume check. If fuel volume is okay, replace fuel pressure regulator.
- If fuel pressure is greater than specification, remove return hose from pressure regulator and place in a container. Repeat test. If system pressure is okay, check for restricted fuel return line. If pressure is incorrect, replace fuel pressure regulator.
- Turn ignition off. After 10 minutes, residual pressure should be 48 psi (3.4 kg/cm2 ). After 20 minutes, residual pressure should be 46 psi (3.2 kg/cm2 ). If system fuel pressure is low, check fuel pump check valve, sensor plate free play, fuel distributor "O" rings and seats. Replace if necessary. If these components are okay, replace fuel pressure regulator.