Engine Controls - Basic Diagnostic Procedures: Diagnosis Volvo V40 I рестайлинг

VISUAL INSPECTION

Visually inspect all electrical wiring. Look for chafed, stretched, cut or pinched wiring. Ensure electrical connectors fit tightly and are not corroded. Ensure vacuum hoses are properly routed and not pinched or cut. See VACUUM DIAGRAMS article to verify routing and connections (if necessary). Inspect air induction system for possible vacuum leaks. See AIR INDUCTION SYSTEMS in SYSTEM & COMPONENT TESTING - S40 & V40 article.

MECHANICAL INSPECTION

Check engine mechanical condition using a compression gauge, vacuum gauge or engine analyzer. See engine analyzer manual for specific instructions.

Scheme 1

1. Run engine until operating temperature is reached.
2. Remove engine cover. (Scheme 1) Remove cover from over ignition coils.
3. Mark each ignition coil and remove. (Scheme 3) Remove spark plugs. Remove system relay from relay box located behind driver-side strut tower. (Scheme 5)
4. Separate engine speed (RPM) sensor electrical connector. Sensor harness connectors are located on firewall, under cover. (Scheme 2)
5. Install compression tester into spark plug hole of cylinder No. 1. Switch ignition to ON position. Hold throttle at Wide Open Throttle (WOT) position. Switch ignition to START position and crank engine over until compression gauge reads maximum cylinder pressure. Switch ignition to OFF position. Read compression values. Compression should be 160-189 psi (1100-1300 kPa). Maximum compression difference between cylinders is 29 psi (200 kPa). If values are not as specified, diagnose and repair as necessary. If values are OK, go to next step.
6. Repeat procedure in step 5 for all cylinders. Go to next step.
7. Install components when compression check is complete. Tighten spark plugs to 18 ft. lbs. (25 N.m). Tighten ignition coils to 89 INCH lbs. (10 N.m). Install ignition coil cover and engine cover and tighten fasteners to 72 INCH lbs. (8 N.m).
8. Start engine and check for proper function. Retrieve and diagnose DTCs using scan tool.

Scheme 2

Scheme 3

Testing While Driving Vehicle

Note. Use foam padding or clean shop towels to protect vehicle interior and body.

1. Remove fuel rail cover. Connect Fuel Gauge (999-5011), or equivalent, to Adapter Hose (951-2614), or equivalent. (Scheme 6) CAUTION: Ensure that hose follows rubber intake plenum trim and exits engine bay at rear corner of hood. Fuel gauge "T" valve MUST be outside closed hood. Incorrect arrangement will cause vehicle damage.
2. Remove cap from fuel line fitting and attach Adapter Hose loosely. Place foam pad or shop towel between T-valve and mirror. Attach T-valve to left mirror using strap-ties.
3. Connect fuel drainage hose to T-valve to prevent fuel from spilling past T-valve directly onto vehicle.
4. Tighten Adapter hose fitting onto fuel rail. Turn ignition on and wait for fuel gauge to indicate starting fuel pressure.
5. Start engine. Ensure that no more fuel will spill past "T" valve and remove fuel drain hose.
6. Drive vehicle and read fuel pressure. Pressure should be approximately 32-45 psi (220-310 kPa). Pressure should be stable at constant load and should fluctuate during acceleration or engine braking. If not as specified, locate and repair fuel pressure leak. If pressure is OK, go to next step.
7. Turn ignition off. Attach drain hose to "T" valve. Remove strap-ties from fuel gauge and open vehicle hood. Place Gauge inside engine compartment to prevent spilling fuel on vehicle body during removal.
8. Place a container below fuel rail. Remove adapter hose fitting from fuel rail and wait for hose to finish draining before moving. When pressure checking equipment is removed, install cap onto fuel rail fitting. Install fuel rail cover.

Scheme 4

FUEL TANK SYSTEM PRESSURE TEST

Fuel Filler Cap Pressure Test

Test fuel filler cap. Test at low pressure of 0.73-1.4 psi (5-10 kPa). Test at high pressure of 2.2-3 psi (15-20 kPa). Replace cap if it does not hold specified pressures.

Fuel Filler Cap Pressure Leakage Test

Slowly pressurize fuel filler cap to approximately 0.4 psi (3 kPa). Allow pressure to stabilize. Pressure must not decrease by more than 0.2 psi (1 kPa) within 30 seconds. If pressure drop is above specification, replace filler cap.

Fuel Filler Cap Vacuum Leakage Test

Slowly create vacuum of approximately -0.4 psi (-3 kPa) in fuel filler cap. Allow vacuum to stabilize. Pressure must not increase by more than 0.2 psi (1 kPa) within 30 seconds. If pressure increase is above specification, replace filler cap.

Scheme 5

1. Check canister purge valve. Remove valve and disconnect hoses. Connect Vacuum Pump (999-5843) to tube marked "B". see scheme 11 Vacuum gauge should read vacuum while pumping (resistance should be felt) and quickly return to atmospheric pressure once pumping is stopped. Air is admitted into purge valve through tube marked "A". see scheme 11 If air is felt and heard through tube marked "A", go to next step. If not, go to step 4.
2. Connect Vacuum Pump (999-5843) to tube marked "A" and pump until vacuum is achieved. Vacuum should remain constant. If vacuum remains constant, go to next step. If not, go to step 4.
3. Connect canister purge valve electrical connector while vacuum pump is connected to tube marked "A". Vacuum should reduce. If vacuum does not reduce, go to next step. If vacuum reduces, canister purge valve is OK.
4. Replace canister purge valve. See «EVAP CANISTER PURGE VALVE»(ref-159330-S31760296972003112600000) in REMOVAL & INSTALLATION - S40 & V40 article. Repeat procedure in step 1.

Scheme 6

1. Raise and support vehicle. Disconnect leak diagnostic pump rear hose marked "A" and fit a piece of hose and plug over the hose connection. Disconnect pump front hose marked "C" and fit Pressure Regulator (999-5646) to pump. see scheme 12 NOTE: Hang manometer vertically to ensure accurate measurement.
2. Connect Manometer (999-5230) to Pressure Regulator (999-5646) and connect compressed air supply. Set pressure regulator to a maximum of 3 psi (20 kPa). see scheme 12
3. Pressurize system for 5 minutes. Close regulator valve when pressure exceeds 3.7 psi (25 kPa).
4. Disconnect compressed air and monitor pressure in system for 30 minutes. Pressure must not drop below 2.5 psi (17 kPa). Feel and listen for air leakage from rear pump hose (marked "A") and from around diagnostic pump. see scheme 12 If pressure drop exceeds specification, there is an internal leak in diagnostic pump. Replace leak diagnostic pump. See «LEAK DIAGNOSTIC PUMP»(ref-159330-S23726091852003112600000) in REMOVAL & INSTALLATION - S40 & V40 article. If pressure remains as specified, pump is OK. Go to next step.
5. Remove manometer, regulator and plugs from diagnostic pump. Fit diagnostic pump hoses onto pump and ensure proper seal. Use a NEW clamp for front hose.