Fuel System Diagnostics

Checks	Action
Before Using This Section	Before using this section, you should complete the following: - The ECU is operating correctly - There are no DTCs stored or existing in the memory Several of the following symptom procedures call for a careful visual and physical check. These checks are very important as they can lead to prompt diagnosis and correction of a problem.
Fuel System Checks	1. Verify the user's complaint 2. Locate the correct DTC table 3. Check the items indicated under the symptom 4. Operate the vehicle under the conditions the symptom occurs 5. Take a datalog screenshot under the condition that the symptom occurs to review at a later time
Visual & Physical Checks	- Check all CORE system fuses and relays - Check all CORE grounds for being clean, tight, and in their proper locations - Check the vacuum hoses for splits, kinks, and proper connections - Check thoroughly for any type of leak or restriction - Check for air leaks at all mounting areas of the intake manifold sealing surfaces - Check for proper installation of the mixer assembly - Check for air leaks at the mixer assembly Check the ignition wires for the following conditions: - Cracking - Hardening - Proper routing - Carbon tracking - Check all wires for any pinches or cuts