Aloha, new here and seeking advice from the pros! CRANK NO START, SPUTTERING. I bought a 2003 Ranger XLT 4.0 4x4 as a project truck from original owner. It had 293K on it and he stopped driving it as soon as it developed the timing chain slap. Started right up and ran fine, i had it towed home. I found a donor 2003 Mazda B4000 4x4(identical truck) with 78k to swap engine, transmission, transfer case, front differential(rear dif already gone), Y pipe(with cats), throttle body(with sensor), intake manifold(was cleaner). The history of this Mazda is unknown other than it had sat for a few years and wouldn't fire but the owner would turn it over a couple times a year to keep it lubricated.

I pulled the engine on the donor and did the timing job with a cloyes kit(but OEM tensioners) and the special timing tools. Using the special timing tools makes timing this engine foolproof and I'm confident it's perfectly timed. All of the internals looked great other than one right bank timing chain cassette broken but no visible damage to pistons or valves/heads. Cylinder walls look new, no burnt oil and all clean reflecting the low mileage. I dropped it in and no start. Had low compression in 2 cylinders(125,180,195,185,200,155) wet compression then leakdown showed leaking exhuast valves. Pulled apart and all exhaust valve faces had carbon deposits and minor pitting, seats weren't terrible and all intakes looked good. I had the machine shop replace all exhaust valves, guides, and cut seats on exhaust only. Re-timed with special tools and back in truck.

Compression between 175-190 on all cylinders cold, good to go. Brand new motorcraft injectors, plugs, wires, ignition coil. Verified spark on all cylinders, fuel pressure at schrader valve on fuel rail 60-62psi and holds pressure. It will not fire and only sputters. Did 50/50 test with starting fluid, same. All new plugs are black/sooty and smell like gasoline, slightly wet(as pictured). I have swapped MAFS, IAC, TBS, Crank sensor, Cam sensor with original known working ones and nothing changes. The only thing I can think of is the PCM. I may have diconnected the battery with the ignition on a couple times and have read that could harm the PCM? What am i missing? The truck originally fired up and ran, the only variable now is this donor engine. With good compression across all cylinders shouldnt the engine internals be good and in time? I am an experienced backyard mechanic but by no means an expert. PLEASE HELP!!! Thanks in advance for any replys and thanks for reading. Mahalos!!!!