I just went though the same thing! I Read all about the possible problems I could find. The FPR seemed to fit the best. I checked the FPR using a vacuum sucker tool. FPR would not hold vacuum. R&R FPR engine ran good for about 4 minutes. then engine started running rich on all 4 cyl. Long story/short engine oil was mostly fuel! When the oil got hot it would vaporize the fuel. Changed oil and filter, FPR and all is well.
My 2 cents Chuck