Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Symptom Related Diagnostic Procedures

NOTE: Excessive fuel tank pressure could be caused by the fuel cap and does not necessarily indicate a problem with evaporative system components.

1. Visually inspect components for:

Mechanical
- Fuel odor or leakage

- Damaged vacuum or fuel vapor lines

- Loose vapor line connections

Electrical
- Discharged battery

- Damaged connectors

- Damaged air flow meter/sensor

- Damaged or inoperative canister purge solenoid

2. Exercise wiring to connector for canister purge solenoid. Check throttle body, air flow sensor, and the Powertrain Control Module (PCM) for looseness, corrosion, damage or other problems.

3. Check fuel tank, fuel vapor lines, vacuum lines, and connections for looseness, pinching, leakage, damage or other obvious causes for malfunction.

4. If malfunction is not detected during visual inspection, proceed with Evaporative Emissions Pinpoint Test. Pinpoint Tests