Vehicles Affected:
Condition:
Some vehicles will have the following conditions:
One or more of the following DTCs set:
Cause:
This condition may be caused by major carbon build-up on the intake and/or exhaust valves due to fuel contamination or incomplete burning of the fuel as shown below, so the misfires should not have appeared until accumulated at least 8,000 km (5,000 mi) or more
Correction:
Note: Trying a different, high-quality Top Tier fuel and regular oil changes is sometimes the best diagnostic. Additional gasoline retailers are added to the TOP TIER list when their gasoline meets the TOP TIER Detergent Gasoline Standards.
Service Procedure:
1. Fill Cleaner Kit J-35800-A with Top Engine Cleaner, approximately 473 ml (16 oz), and close the cap of the tool tightly. Set the air pressure to 260 kPa (40 psi) at the service tool.
2. Using GDS 2 or a Scan Tool, command engine idle to 2000 rpm to prevent the engine from stalling. Typically, 2,000 rpm will be sufficient.
Note: Two applications of the Top Engine Cleaner may be necessary to perform a total cleanup depending on
the condition of the combustion chamber.
3. In a well-ventilated area with the engine at operating temperature, slowly/carefully induce the Top Engine Cleaner into the engine, which should take approximately 3 minutes.
⇒ For best results, it is suggested to induce the cleaner through the throttle body with Fuel Injector Cleaner Kit J-35800-A or equivalent and NEW Cleaner Nozzle EN-35800-20, which has been developed to help atomize the
cleaner.
4. After the entire contents of Top Engine Cleaner has been induced, continue to run the engine for 2
minutes at idle.
5. Change the engine oil and filter, and only use one of the Top Tier to minimize future deposits. It can also be recommended to add a bottle of GM Fuel System Treatment Plus at every oil change.
6. Test drive the vehicle, using only light acceleration, and clear any DTCs if necessary