Lower Limit
Special Tools:^ 981 4215
^ 999 5843
Checking Mass Air Flow Sensor
- Ignition ON.
- Connect a voltmeter between mass air flow (MAF) sensor connector terminals 2 and 4.
- The voltmeter should read 0.1 - 0.2 Volts.
If reading is OK:
^ Proceed to: Checking for Air Leakage in the Exhaust System section below.
If reading is incorrect:
^ Try a new mass air flow sensor.
Checking for Air Leakage in the Exhaust System
- Check for air leakage.
- Check for air leaks in the exhaust system.
- Is there any air leakage?
No:
^ Proceed to: Checking the Fuel and Residual Pressure section below.
Yes:
^ Remedy as necessary.
^ Continue by erasing diagnostic trouble code (DTC).
Checking the Fuel and Residual Pressure
- Check fuel and residual pressure.
- Is fuel pressure OK?
Yes:
^ Proceed to: Checking Canister Purge Valve section below.
No:
^ Remedy as necessary.
^ Continue with erasing diagnostic trouble codes and resetting adaptive functions.
Checking Canister Purge Valve
- Remove hose to intake manifold from canister purge (CP) valve. Reinstall hose after fault-tracing.
- Connect vacuum pump 999 5843 to canister purge valve connector.
- Pump up a vacuum. The vacuum gauge should indicate a steady vacuum.
If reading is OK:
^ Proceed to: Checking Engine Oil Level section below.
If reading is incorrect:
^ Try a new canister purge valve.
^ Continue with erasing diagnostic trouble codes and resetting adaptive functions.
Checking Engine Oil Level
- Check engine oil level.
- The oil level should be between the MIN and MAX marks.
If reading is OK:
^ Proceed to: Checking Engine Oil section below.
If reading is incorrect:
^ Proceed to: Fault-tracing Information section below.
Fault-tracing Information
- Ensure that the oil level is correct.
- Proceed to: Checking Engine Oil section below.
Checking Engine Oil
- Start the engine and idle it for a few minutes.
- Go into scrolling values.
- Read off and note short-term fuel trim value.
- Disconnect and plug crankcase ventilation.
- Read off the short-term fuel trim value again.
- This value should be more or less the same.
If reading is OK:
^ Proceed to: Connecting the Breakout Box section below.
If reading is incorrect:
^ This indicates that the engine oil is contaminated with fuel.
^ Change engine oil and oil filter.
^ Continue by erasing diagnostic trouble codes and resetting long-term fuel trim.
Connecting the Breakout Box
- Connect the breakout box and check ground terminals.
- Connect engine control module.
- Check all signals to and from engine control module.
- Proceed to: Verification section below.
Verification
After carrying out the repair, check that the fault has been remedied as follows:
- Ignition OFF.
- Reconnect connectors and reinstall components.
- Go into scrolling values.
- Read off the long-term fuel trim value.
- Test drive the car.
- Watch the long-term fuel trim value until it switches to completed.
- If EFI-231/232 are stored they should have intermittent status.
Yes:
^ Fault corrected.
No:
^ Proceed to: Fault-tracing Information section below.
Fault-tracing Information
The verification result shows that the fault persists.
- Do you want to exit fault-tracing?
Yes:
^ Fault not corrected.
No:
^ Proceed to: Checking Mass Air Flow Sensor section above.