pm2 process manager not working

I install the pm2 using npm install -g pm2 then when I run my node application using 

pm2 start app.js

nothing is happening. when I run the command in terminal, it just go down another line. No errors or warnings shows in the terminal. I can run the application using nodejs app.js . Any kind of help would be appreciated. Thanks.

I suppose it happens because of the node.js executable, if you are in Ubuntu install nodejs-legacy to enable the correct "node" executable link, I think pm2 is trying to use this one.

  1. use ps aux|grep node check the node is already running?
  2. use pm2 list check you process is running?
  3. check the pid file of you process and do the needful, kill may be.