For 1990-2009 cars only
| • | Loose or broken crankshaft balancer or accessory drive pulleys. |
| Refer to Drive Belt Diagnosis . |
| • | Excessive piston-to-bore clearance. Replace the piston and pin. |
| Refer to Piston Selection . |
| • | A cold engine knock usually disappears when the specific cylinders secondary ignition circuit is grounded out. |
| Cold piston knock which disappears in 1.5 minutes should be considered acceptable. |
