Rough Running or Misfire

NOTE: If the vehicle exhibits any of the following symptoms and an emission component is suspect, be sure to visually inspect the following before any tests are performed:


1. Vacuum hoses for leaks, splits, kinks and proper routing.
2. Ignition wires for cracking, hardness and proper connection at the distributor and sparkplugs.
3. Wiring harnesses for proper routing and connection.

Determine if any fault codes are stored in the ECM. Correct any faults indicated before proceding.

SYMPTOM:

ROUGH RUNNING OR MISFIRE
Check:
1. EGR System
2. PCV System
3. Fuel Injector
4. Fuel Pressure Regulator
5. TDC/CKP/CYP Position Sensor
6. Manifold Absolute Pressure Sensor