Complaint/Condition | Possible Causes | Corrections |
|---|---|---|
Momentarily Noisy When Engine is Started | This condition is normal. Oil drains from the lifters, which are holding the valves open when the engine is not running. It will take a few seconds for the lifters to fill after the engine is started. | Incorrect/faulty oil filter. |
Intermittently Noisy on Idle Only. Disappearing When Engine Speed is Increased. | Dirt in hydraulic lifter or low oil pressure | Disassemble and clean (SOHC Engine). Replace lifter (DOHC Engine). |
Pitted or damaged check valve | Replace the hydraulic lifter. | |
Noisy at Slow Idle or With Hot Oil. Quiet at High Engine Speeds or with Cold Oil. | High leak down rate or low oil pressure | Replace the hydraulic lifter. |
Noisy at High Speeds, Quiet at Low Speeds. | High Oil Level: Oil level above the FULL mark allows crankshaft counterweights to churn the oil into foam. When foam is pumped into the lifters, they will become noisy since a solid column of oil is required for proper operation. | Drain oil to proper level. |
Low Oil Level: Oil level below the ADD mark allows the oil pump to pump air at high speeds which result in noisy lifters. | Add oil as needed. | |
Oil pan bent against oil pump pick-up screen | Repair. | |
Oil pump screen bent or loose | Repair. | |
Engine Starts Normally, But Stalls within Five Minutes. Engine Has Low Compression During Initial Cranking after Stall. | Low compression due to hydraulic lifters being pumped up | Incorrect viscosity oil. Refer to Owner's Handbook/Service Manual recommendations. |
Notice: After cylinder block, head, or lifter replacement, it will be necessary to allow the engine to idle for 3-5 minutes. If the lifters are noisy, warm the engine up at less than 200 RPM. After the coolant temperature has reached approximately 85°C (185°F), cycle the engine RPM from idle to 300 RPM for approximately 10 minutes or drive the vehicle 8 kilometers (5 miles) to purge the air. If the air cannot be purged, the faulty lifters will have to be replaced.
Notice: A noisy lifter or belt tensioner can cause the knock sensor to retard spark timing, reducing vehicle performance and fuel economy.
Lifters that are pumped up may cause PCM misfire codes to set. Continue to operate the engine until the lifters bleed down. Using the PDT, clear codes and malfunction history.
