Engine almost dies on hills and left turns

This is an awsome site with some great info so thanks guys. I have a 1992 MPV 6 cyl 2wd. When I'm making a left hand turn or going up a steep hill it seems like Im running out of gas but then kicks back in when I stop turning. It seems to get worse as my fuel gets lower but that info could be misleading since I've only had this van for a week or two. I've replaced the fuel and air filters with no change. Now the van is sitting on a somewhat steep hill and will start, idle perfectly for a few seconds and then die. It runs great in a straight line or right turns on a flat road and even small inclines, just not left turns or steeps inclines. Any suggestions what I should start looking at? Thanks for any help and happy 4th.

Does sound like  engine is getting starved for fuel under those conditions threeofive. Problem is that I think the pump is more towards the rear of the tank so would expect it to draw some air if you were going downhill and not up. Perhaps there is some debris or water is the tank that is clogging up the pick-up screen under those conditions. Would sure be worthwhile to pull the pump out and see if there is anything else in there besides clean fuel. Also check for anything on the screen sock. There is an access hole for the pump under the carpet that is underneath the middle seat I think. Has been some time since had to get to one so could be wrong on that location. Will try and check on my 91 4X4 and see if can get some better confirmation on that location.