Lower end noise on an 01 is likely to be tensioner guide related, in one way or another.
Plastic tensioners, no latch, and crumbly plastic guides. Search, there are pix all over the web, in all the "Donor Vehicles" forums.
I did this to my 03 engine:
There is an even later revision to the guides; get the latest ones. I'll replace them when I take the cover off to do cams, lol.
If The tensioner guide is making the noise, damage May be minimal, and the whole engine is ok.
If it died due to oil pressure, then the heads are toast, as well as it having (probably) rod knock due to dead bearings...
Pieces of the guide clogging the intake have been found in early PI engines; the heads are Way more oil sensitive than the lower end.
If the lower end was waste, the cam journals are too. YMMV.
Red '96 Cougar XR-7 240k mi. '02 4R70W, PST DS : '03 PI engine, 04 maf, 24lb injectors, 2.5" exhaust, '02 4r70w + Jmod, DirtyD0g TC + cooler + 3/8" lines, 255 walbro fp. Alpine system.
Black '96 Cougar XR-7 (Lazarus) 210k mi PI Intake, '02 4R70W, Jmod, PST DS, GrogTune, Konis, Mark LCA+Poly, racecougar Custom Engine Chain, and JL and racecougar Bracing.
Black '97 Tbird Limited Edition, '02 4R70W, 255 walbro, PST DS, PBR Brakes&SS lines, Toicko Blues & Springs, GrogTune.
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