check engine light blinks 2 times then 5 times after changing alternater belt

Hello, That is code 25, and it means you have a lean fuel mixture, so the engine control module is dumping extra fuel into the engine. You also might actually have an issue causing a lean condition as well, which could be anything from a vacuum leak to a clogged fuel injector. Start by testing the O2 sensor and the circuit, then move on to looking for vacuum leaks.