Finally got the power back in my stroker....been down for 2 weeks.
Stock 97 F-350 7.3L, Auto with 152k
At the beginning, i started using B100, after about 3 tanks, engine lost power, switched to front tank with dino fuel and power returned. I thought I had some bad biodiesel in that tank. Decided to add 6 gal's B100 to front tank and instant power loss, and fuel gauge went crazy when around 1/2 tank.
Changed fuel filter, cleaned return screen, upgraded to new cam position sensor, unplugged map sensor, removed rear fuel tank and found a few ounces of water in fuel and a lot of algae growth, washed out tank at car wash, removed water and flush with gasoline. Pickup strainer had a lot of algae under pickup screen, removed pickup strainer and cleaned, reassembled and installed. Same symptom, no power and a violent shake if stomped accelerator. Measured fuel pressure at 45 psi and thought that was good, decided to change fuel lift pump, cleaned bottom of filter bowl and removed a lot of algae growth, pump change wasn't as hard as I thought it would be, didn't have to pull turbo. Have not measured pressure yet, since it was after dark... will do that tomorrow. Believe the viscosity of the bio was working the pump harder and just failed on bio, it was just enough to revile weak lift pump.
LIFT PUMP FIXED LOST POWER PROBLEM and I am a happy biostroker again!
Now all I have to do is remove front tank, clean and check sending unit.