Intermittent Prob

[1985318i]

Help!
I have a 1985 318i. With time, it got more difficult to start when warm, so I did some troubleshooting. I found it was the in-tank fuel pump, and replaced it. It ran better for a few days, now it's doing something new.
If can drive 4 miles away(It runs fine), and park it for about 45 minutes. When I'm driving home the car will die about 1/2 way home. After it dies, it's difficult to restart, but will after some persistence.
When driving on the highway, the car will also have power surges, however, it doesn't die.
Any ideas??

MUCH THANKS

[theratdude64]

clog/loosing power in the fuel system maybe?

[Hypnogaja]

check the regulator, sounds like the system is losing pressure. Usually when a pump goes out, the regulator dies as well (crap gets in thr diaphram).