SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSCHEVROLET2008CHEVY EXPRESS G3500, VAN PASSENGER EXTENDEDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT VARIANT/TRIMSECTION 4 (ENGINE CONTROL SYSTEM & FUEL SYSTEM - 4.3L - INTRODUCTION (2 OF 2))REPAIR INSTRUCTIONSFUEL INJECTOR CLEANINGCLEANING PROCEDURE
2008 Chevrolet Chevy Express G3500, Van Passenger Extended

Cleaning Procedure

2008 Chevrolet Chevy Express G3500, Van Passenger ExtendedSECTION Cleaning Procedure
WARNING: This page is about a different variant/trim than selected.
    Fig 1: Identifying Fuel Injector Cleaner
    GM651337Courtesy of GENERAL MOTORS CORP.
  1. Obtain J 35800-A  (2).
    2. IMPORTANT: Make sure the valve at the bottom of the canister (3) is closed.
  2. For 4, 5, and 6 cylinder engines, empty two of the 30 ml (1 oz) reservoirs of the GM Upper Engine and Fuel Injector Cleaner twin reservoir container into the J 35800-A  , injector cleaning tank, then add 420 ml (14 oz) of regular unleaded gasoline. If you are using any other brand of cleaning tank, you will need a total of 60 ml (2 oz) of GM Upper Engine and Fuel Injector Cleaner mixed with 420 ml (14 oz) of regular unleaded gasoline.
  3. For 8 cylinder engines, empty two of the 30 ml (1 oz) reservoirs of the GM Upper Engine and Fuel Injector Cleaner twin reservoir container into the J 35800-A  , injector cleaning tank, then add 420 ml (14 oz) of regular unleaded gasoline. If you are using any other brand of cleaning tank, you will need a total of 60 ml (2 oz) of GM Upper Engine and Fuel Injector Cleaner mixed with 420 ml (14 oz) of regular unleaded gasoline.

    This procedure will need to be repeated for an 8 cylinder engine. The 8 cylinder engines receive 960 ml total fluid-120 ml (4 oz) of GM Upper Engine and Fuel Injector Cleaner and 840 ml (28 oz) of gasoline.

  4. Fill the injector cleaning tank with regular unleaded gasoline. Be sure to follow all additional instructions provided with the tool.
  5. Electrically disable the vehicle fuel pump by removing the fuel pump relay and disconnecting the oil pressure switch connector, if equipped.
  6. Disconnect the fuel feed and return line, if equipped, at the fuel rail. Plug the fuel feed and return line, if equipped, coming off the fuel rail with J 37287  , or J 42964-1  , and J 42964-2  or J 42873-1  , and J 42873-2  as appropriate for the fuel system.
  7. Connect the J 35800-A  to the vehicle fuel rail.
  8. Pressurize the J 35800-A  to 510 kPa (75 psi).
  9. Start and idle the engine until it stalls due to lack of fuel. This should take approximately 15-20 minutes.
  10. Turn the ignition to the OFF position.
  11. Injectors should be flow-tested at this point. If further cleaning is needed, a repeat of the above procedure should be done.

    When the injector restriction returns to zero, proceed to step 12.

  12. Disconnect the J 35800-A  from the fuel rail.
  13. Reconnect the vehicle fuel pump relay and oil pressure switch connector, if equipped.
  14. Remove the J 37287  , or J 42964-1  and J 42964-2  , or J 42873-1  and J 42873-2  and reconnect the vehicle fuel feed and return lines.
  15. Start and idle the vehicle for an additional two minutes to ensure residual injector cleaner is flushed from the fuel rail and fuel lines.
  16. Pour the entire contents of GM Fuel System Treatment Plus, GM P/N 88861011 (Canadian P/N 88861012) into a nearly empty tank and advise the customer to refuel with up to 76 L (20 gal) of fuel.
  17. Advise the customer to use only a Top Tier Detergent gasoline and to add a bottle of GM Fuel System Treatment Plus to the fuel tank at every oil change.

    Regular use of GM Fuel System Treatment Plus should keep the customer from having to repeat the injector cleaning procedure.

  18. Road test the vehicle to verify that the customer concern has been corrected.
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

Shop Manual-Ready ToolsFree Quote CheckQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.