A key pressed all the time, but keyboard is unpluged?

Hi. Thanks for your time.

This Hp compaq presario M2000 was wet with coffe (...i know...) and keyboard was writing without pressing it... (iiiiii key all the time).

I took it out and cleaned both contects with isopropyl and it went fine for 2 weeks. But The same problem came back.

I have order a new keyboard and when i have replace it,

The new one has the same problem than older.

I have unpluged the keyboard and started the laptop with NO keyboard and the iiiii key, as always is being pressed all the time. Must be a very little short somewhere?

Is there something else i can do/ Clean?

Thanks.