Standard Procedure - Engine Performance

WARNING: This page is about a different car, the 2003 Jeep Wrangler. However, it is still accessible from the selected car via links, so may be relevant.

It is important that the vehicle is operating to its optimum performance level to maintain fuel economy and the lowest emission levels. If vehicle is not operating to these standards, refer to DIAGNOSIS AND TESTING . The following procedures can assist in achieving the proper engine diagnosis.

Test cranking amperage draw. (Refer to STARTING - DIAGNOSIS AND TESTING ).
Check intake manifold bolt torque (Refer to INTAKE MANIFOLD - INSTALLATION ).
Perform cylinder compression test. (Refer to ENGINE - DIAGNOSIS AND TESTING ).
Clean (Refer to SPARK PLUG - CLEANING ) or replace spark plugs (Refer to SPARK PLUG - REMOVAL ) as necessary.
Test coil output voltage and primary resistance. (Refer to IGNITION CONTROL - SPECIFICATIONS ). Replace parts as necessary.
Test fuel pump for pressure. (Refer to FUEL PUMP - DIAGNOSIS AND TESTING ).
The air filter elements should be replaced as specified.
Inspect crankcase ventilation system.
Road test vehicle as a final test.