Starter

Thursday night I made a starter for a stout I'm brewing this weekend.
150g DME and 1.5l water, brought to boil and cooled to ~70f.
Pitched vial of yeast, WPL004 Irish Ale Yeast, at the same temp, had been in my fridge for a few days prior.
Next morning, no activity. That evening, no activity. This morning, no activity.
No krausen, no yeast in suspension other than caused by the stir plate.
Check the gravity just to be sure...1.004
I thought I had gotten a bad vial but apparently something has happened. Also, no noticeable increase in yeast volume.

Thoughts?

You should be fine. If I did my math right it looks like you had enough extract in the starter, and it fermented down. Go ahead and pitch.

Most of the time when I make my starters I see little to no activity. There were a few times when I have had an explosion of krausen.. You will be fine..

This was really bothering me so I made a new starter, same ratios. Decanted the beer off the yeast and dropped the new wort on. Krausen formed withing a couple hours and started overflowing out of the top of the flask. I don't really understand why. My starters have all been closer to the latter in terms of activity, was the first just a fluke?

If you went from 1.040 which your starter ratio would create and you then got a reading of 1.004 it fermented and I'm not sure why you panicked (unless it was a typo)

I've had lots of starters show no evidence of big krausen and be fine, especially on my stir plate. I do find if you use too fast a speed on the plate evidence of krausen is far less but I can still usually see a very thin line just above the wort level when off.