To determine if a faulty fuel injector is causing the cylinder to misfire, perform the following steps:
1. Connect to DDDL 7.0.
2. Start the engine.
3. From the Select Menu, scroll to select ENGINE and press the ENTER key.
4. Scroll to FUEL INJECTOR INFO (CUTOUT) and press the ENTER key.
5. Scroll to select NEW TEST and press the ENTER key.
6. Scroll to select RPM SETTING FOR CCO TEST NORMAL and scroll to select 1000
and press the ENTER key.
7. Scroll to select AUTO and press the ENTER key. Wait for END OF TEST.
NOTE:
If an injector cannot be cutout, you will see an ERROR message. Press FUNC to exit the cylinder cutout function, press the FUNC key.
8.Scroll the list to review the results of the cylinder cutout test. To find suspect injectors, look for a cylinder with a value that is within 0.2 degrees of the NO CUTOUT PULSE WIDTH, by comparing the CUTOUT PULSE WIDTH values to the NO CUTOUT PULSE WIDTH values.
[a] If any CUTOUT PULSE WIDTH values are within 0.2 degrees of the NO CUTOUT PULSE WIDTH, shut down the engine and refer to section 3.3.1.
[b] If any CUTOUT PULSE WIDTH values are not within 0.2 degrees of the NO CUTOUT PULSE WIDTH, shut down the engine and refer to section 3.4.
3.3.1
Faulty Fuel Injector Repair
Perform the following steps for faulty fuel injector assembly(s):
1. Remove and replace injector assembly(s) whose values are within 0.2 degrees of the NO CUTOUT PULSE WIDTH; refer to the appropriate service manual, fuel system chapter.
2. Verify replaced injector assembly(s), refer to section 3.3.1.1.
3.3.1.1
Verification of Repair for Faulty Fuel Injector
Perform the following steps to determine if the replaced fuel injector(s) resolved the misfiring
cylinder condition:
1. Refer to section3.3 for the exhaust caution before preceding. Start the engine.
2. Run the engine speed up to the occurrence of the misfiring.
3. Listen for misfiring cylinder.
[a] If the engine is not misfiring, shut down the engine. No further troubleshooting is
required.
[b] If the engine is misfiring, shut down the engine and check for a faulty Electronic
Control Unit (MCM); refer to section 3.4.
