Workshop Manuals Factory service & repair Alfa Romeo
Alfa Romeo 155 Factory Service Manual (1992-1998)08 · Fuel system (V6)
08 · Engine

The engine runs irregularly

Make
Alfa Romeo
Model
155 Factory Service Manual
Year
1992–1998
Section
The engine runs irregularly › The engine runs irregularly
Fuel system (V6)The engine runs irregularly

THE ENGINE RUNS IRREGULARLY

TEST PROCEDURE RESULTS CORRECTIVE ACTION
H4 CHECK ALTERNATOR
OK
 Proceed to phase H5
- Check that the alternator is working correctly and in particular the voltage regulator. The alternator must not be overloaded. See ELECTRICAL - ELECTRONIC DIAGNOSIS manual
NOT OK
 Replace the voltage regulator or alternator if faulty
H5 CHECK FOR LEAKAGE OF AIR
OK
 Proceed to phase H6
- Check:
  • that air is not escaping from the circuit. Cover the connections along the pipes downstream of the airflow meter with soap solution. With the engine at idle speed check that the solution is not sucked in by the engine
  • the correct air flow: see GROUP 04 - CHECKING THROTTLE VALVE CALIBRATION
NOT OK
 Replace the faulty components
H6 CHECK AIR-FLOW METER
OK
 Proceed to phase H7
- Check that the tabs move freely without bending. Check that there are no traces of dirt or rubbing inside
NOT OK
 Replace (or clean) the meter
H7 CHECK FUEL PRESSURE
OK
 Proceed to phase H8
- Check the pressure and sealing of the fuel supply circuit - see GROUP 04 - FUEL CIRCUIT PRESSURE AND SEALING CHECK
NOT OK
 Check that the fuel filter, pump and pressure regulator are working correctly and replace any faulty parts
H8 CHECK FUEL FILTER, PUMP AND PRESSURE REGULATOR
OK
 Proceed to phase H9
- Check that the fuel filter, pump and pressure regulator are working correctly and replace any faulty parts
NOT OK
 Check that the fuel filter, pump and pressure regulator are working correctly and replace any faulty parts

(CONTINUES)

Parts & tools for this job For 1992 Alfa Romeo 155

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