If the car bounces up and down more than twice, you may need new shock absorbers. Examine the engine for excessive fluid leaks. Check the radiator and battery for proper fluid level and cracks. Oil in the radiator is a sign of a cracked block, blown cylinder head gasket, or leaking transmission cooler. Check the oil dipstick.
Black sludge is a sign of neglect.
Water droplets or gray foam in the oil mean that the block has cracked. Check the trunk area for rust, a working jack and a spare tire. Check the interior for wear on the seats, floor mats, and pedals. Look for water marks and musty odors, rust, sand under the rugs, and corroded electrical connectors- all signs that the car was in a flood. That Is Flood-Damaged.