1985 300D Turbo loss of power after 25 mins

[waldos313]

My wife has been driving our 85 the 35 mile trip to work everyday and has had the same problem twice now in the last couple days. After about 25 mins of driving at 70 mph, the car would lose power like a clogged fuel filter. I drove it today and it started to do the same thing after about 30 mins of driving when I floored it up a steep hill near our house at about 55mph. The fuel filters are both fresh with a new priming pump and the air filter is clean.
I have not bench tested these injectors yet but the car has wonderful, smooth power until the above problem occurs and consistently gets greater than 25mpg. It runs at 80-90* C consistently as well. We are running it on veggie oil. I also have not checked the fuel tank strainer.
Please help! I already ordered Monark nozzles for it and will install those and clean the fuel tank strainer next weekend.
Any ideas??!!
Brandon
Pensacola, FL
1979 300D "Red"
1985 300D Turbo "Blue"