Engine "coughing" - dies going even slightly uphill

[levity03]

Hi,

My P50 is having some issues and I'm not too mechanically engine savvy so layman's terms preferred!  It started this weekend and got to the point where it's hardly running at all, even on flat ground. 

Going uphill, it coughs and eventually dies.  On flat ground, it does this to a certain extent, unless I'm only giving it a little bit of gas but once I go passed that amount, it sounds like it's going to die again.

Any ideas on what could be the problem - I'm going to either try to fix it myself if it's an easy fix or at least be educated when I go to get it fixed. 

Thank you!!

[sidthesloth]

Does it start spluttering and bogging down? If so, it could be your air filter, a good wash and re~oil should fix it. If the filter is restricted, it will cause the engine to run a rich fuel mix (too much fuel, not enough air).

[levity03]

Yea, that's what it does. Doesn't take long to completely shut down when going up a hill but when I'm going on flat ground, I can accelerate just enough so it doesn't try too hard and shut down. 

I'll try and clean it with some solvent - any suggestions on which to use?  Also, what fuel grade should I be using?

Thank you!!

[levity03]

UPDATE:

So, I've cleaned the air filter and replaced it and now it won't start.  It sounds like it's choking! Too much oil in the oil/air mix?

Any ideas of next steps?