fuel trim adaptation additive bank 1

Fuel trim addative indicates that the car is running lean. The car only has one bank because it is a four cylinder. You are going to have an air leak in the intake air system down stream of the air mass meter. You can inspect the large rubber boots attaching the air meter to the intake manifold. Also look two rubber tubes attaching to a black valve on the top of the intake that run to the rear of the valve cover. These crankcase venting tubes and the valve (intake runner control) on the left side of the intake are common leaks. The best way to correct the leaks is to have the intake manifold smoke tested for leaks. It is not a very involved test. The smal investment in the test will save you time and money by accuratly diagnosing the leaks.

We did a test and it said 'Fuel Trim Adaptation Additive Bank 1 High Code number P1159'. Does anyone know what this code stands for?