Warning signs the Upper Engine Cover is failing:
- Oil leaks around the engine cover area.
- A burning smell coming from the engine.
- Unusual engine noises, like hissing or rattling.
- Visible cracks or damage to the engine cover.
- Engine misfires or rough idling (in severe cases).
How to test if this part is the problem:
- Visual Inspection: Carefully check the engine cover for cracks, warping, or other damage.
- Leak Check: Look for oil residue or wet spots around the cover's edges. Clean the area and monitor for new leaks.
- Pressure Test: A mechanic can perform a pressure test to check for leaks in the engine's crankcase ventilation system. This test can help pinpoint leaks coming from the cover.
- Listen Carefully: While the engine is running, listen for unusual noises near the engine cover. A hissing sound could indicate an air leak.
Common failure causes for this part:
- Heat and age: Over time, the plastic material can become brittle and crack due to exposure to high engine temperatures.
- Oil exposure: Constant exposure to engine oil can degrade the plastic.
- Improper installation: Over-tightening bolts can crack the cover.
- Physical damage: Impacts or accidents can cause cracks or breaks.
- Clogged PCV valve: A clogged PCV valve can cause excessive pressure in the crankcase, leading to leaks or damage to the engine cover.