Due to the high temperatures under the hood of a vehicle, rubber and plastic hoses in the engine compartment, as well as accessory and emission systems must be regularly checked for signs of wear and tear. Look out for cracks, loose clamps, hardening of material, and leaks. Check that clamped hoses have not lost tension which can cause leaks, and observe whether unclamped hoses show signs of expansion or hardening that may result in leakage. In case the PCV system hose is cracked, leaking or damaged it needs cleaning in case there is any clogging. Inspect plastic T-fittings for cracks and hoses for distortion. Small piece of vacuum hose can be used as a stethoscope to detect leaks. The fuel hose should be checked for damage such as deterioration, chafing and cracking particularly at bends and fittings.