Loss of Power

[FONT=arial]Falls on face over 1500rpm. I recently replaced the center fuel tank on my 86 Ranger 2.9 FI. I reused the original low pressure pump because it was in good condition. The tank came out of a used truck from a bone yard but was in excellent condition and the same size. After installation the truck looses power after 1500rpm no matter what gear. I have replace the HP pump, ignition module, TPS, fuel filter, cleaned and checked the EGR , air bypass and fuel regulator. Upon inspection of the fuel system I noticed what appears to be a round canister inline between the LP and the HP fuel pumps. I can find no info concerning this part. Not from repair manuals nor mechanics seem to know. Does anyone know what the heck it is and what it does? Could this be my problem? The truck starts and idles perfect but has no power upon acceleration. Please Help!!! R-RangerSTX