Other Possible Causes Of DRIVEABILITY Related Problems

At this point in the DRIVEABILITY TESTS you have determined that all of the engine control systems are operating as they were designed. Therefore, they are NOT THE CAUSE OF THE DRIVEABILITY PROBLEM.

The following items should be checked as possible causes:

• ENGINE VACUUM - Must be at least 13 inches in neutral.
• ENGINE VALVE TIMING - Set to specifications.
• ENGINE COMPRESSION - To specifications.
• ENGINE EXHAUST SYSTEM - Must be free of any restrictions.
• ENGINE PCV SYSTEM - Must flow freely.
• ENGINE DRIVE SPROCKETS - Ensure they all are in good condition.
• TORQUE CONVERTER STALL SPEED - To specifications.
• POWER BRAKE BOOSTER - No internal vacuum leaks.
• FUEL CONTAMINATION - Check for high alcohol and water content.
• TECHNICAL SERVICE BULLETINS - Any that may apply to the vehicle.

Any one or more of these items can create a driveability related problem. They can not be overlooked as possible causes.