Hey Guys - I am new to the forum, I just purchased an 88 Samurai around 3 weeks ago.  It was running great for the first couple of weeks but now I am starting to have some problems.   The engine stalls during idle, and it feels like it is getting bogged down when under a load.  I can feather the pedal when not in gear and it the engine runs fine at higher RPMs.   But as soon as I put it in gear and take off it wants to stall out.   I have replaced all of the things a beginner would start with, plugs, wires, cap, rotor, fuel filter and PCV valve.   I don't think its the choke, because it does this even when its ran for 20 minutes.     Not sure if I am loosing compression or not, but just a few days ago I could get it up to 65 MPH.     Any ideas?

I have also changed the air filter and double checked all of the vacuum line connections.   I changed the oil with a blended, was this stupid?

Did you put new plugs, cap are rotor on at the same time as the new air filter?

yes, I did plugs, wires, rotor, cap, air filter, PCV valve all in the same day.  It ran great for around 10 days.  Started getting the problem just this weekend.  could I be running rich?

Sounds like it is a lack of gas, not too much gas.
Try changing the fuel filter.  If that doesn't fix the problem, then there is probably crap in the carb and it is clogging/restricting the jets.  So you'll have to take the carb apart, clean it, adjust it and that will likely fix the problem.