Engine Controls - System/component Tests - Eec: Diagnosis

Engine Controls - System/component Tests - Eec: Diagnosis Ford Escort V facelift

FUEL SYSTEM TESTING

Note. For fuel pressure specifications, see FUEL PRESSURE SPECIFICATIONS article.

Check for engine vacuum leaks. Check for loose or misthreaded fittings, cracks, and blockage which could cause insufficient vacuum supply to fuel pressure regulator. Repair vacuum leaks as necessary. If no vacuum leaks are found, go to next step.
Check fuel pressure regulator housing for damage and dents which could cause a higher spring load on regulator. Check fuel pressure regulator diaphragm operation. See steps 3) and 4) in LOW FUEL PRESSURE TEST. If fuel pressure regulator is okay, go to next step. Replace fuel pressure regulator if defective, and recheck fuel pressure.
Disconnect fuel return line from fuel pressure regulator and fuel tank. Place disconnected hose at fuel tank into an empty container. Using low air pressure (5-10 psi), blow air into disconnected return line at pressure regulator. If fuel return line is restricted, clean or repair return line as necessary and repeat fuel pressure test. If fuel return line is free of restrictions, replace fuel pressure regulator and repeat fuel pressure test. If fuel pressure is still high, go to FUEL INJECTOR TEST.

With engine idling or cranking (no start), use stethoscope to listen for consistent, operational sounds (clicking) coming from each injector. If operational sounds are present, go to FUEL INJECTOR LEAKAGE TEST. If operational sounds are not present, disconnect fuel injector connector and install continuity checker into injector connector. Start or crank engine.
Observe whether continuity checker blinks, indicating completed circuit for injector being tested. Repeat continuity check for each injector. If all injector circuits indicate continuity, go to next step. If any circuit does not indicate continuity, turn ignition on. Check for 12 volts at each injector connector. If 12 volts is present at each injector connector, go to next step. If 12 volts is not present at each connector, repair wiring as necessary.
Using DVOM, check injector resistance. Replace injector if resistance is not about 12-16 ohms at 68°F (20°C). Repeat step 1). If results of step 1) are okay, go to FUEL INJECTOR LEAKAGE TEST. If injector resistance is within specification, go to FUEL INJECTOR LEAKAGE TEST.

Install Fuel Injector Tester/Cleaner (113-00001A). Clean injectors according to tester/cleaner manufacturer's instructions. After injectors are cleaned, check for fuel system pressure loss. On 1.8L and 2.0L A/T, if pressure loss is observed, remove injectors and individually check (bench test) injector leakage rate. Maximum injector leakage rate is one drop per minute. Replace injector if maximum leakage rate is exceeded.
On 2.5L, fuel injectors are side inject type and cannot be bench tested. Disconnect fuel rail from intake manifold, leaving fuel hoses connected. Using jumper wire, connect fuel pump terminal to ground terminal to activate fuel pump. (Схема №5) Turn ignition on for 10 seconds. Maximum injector leakage rate is one drop per minute. Replace injector if maximum leakage rate is exceeded.