I suspect the primary fuel pump.
Both fuses are an easy check.
You may tape a fuel pressure gauge to the windshield, to observe the fuel pressure while cranking. Normal fuel pressure with ignition on but not running, is listed below. At idle or with 10 inches of vacuum, the pressure should drop by 3-10psi (21-69kPa).
You should have a check engine light when turning the key ON, before starting. Grounding the test terminal should give a '12' (indicating a 12v test signal, BTW) then, any trouble codes.
Test A-3 is for: "the engine runs fine until hot, then stalls. I can crank but it will not stay running. After it cools, it starts and runs fine." Sound familiar?
At a coolant temperature above 80C, the secondary fuel pump is deenergized by the ECM. The engine will stall if the CKT 120 or the primary fuel pump are faulty. Below 80C, both fuel pumps are energized. (This is probably like the cold start injector on early port injected cars, later replaced by ECM control.)
Chart A-3: With good spark (a lengthy
process seemingly not applicable), disconnect #2 primary injector (gray) and connect injector test light to the harness. Crank and look for blinking light. No flash means a faulty ECM; Yes> check pre-cranking fuel pressure (48-55 psi, or 333-376kPa).
If good pressure, pull FP2 and check fuel pressure (same). If okay, the fuel injector system is okay. If not, Chart A-7 applies.
If low pressure with FP2 pulled, there is a faulty connection or open CKT 120 (feed from FP1 to pump 1)
The service manual shows: a fuel pump test connector (near the the battery) as a red (#490) wire, feeding the primary fuel pump relay, at terminal 3. #2 is ground. #5 comes from the ECM to trigger the relay, while #4 is power to operate the relay, fed from the fusible link; also feeding the ignition switch and fuse block.
#1 terminal on the Primary fuel pump relay connects (red wire) to FP1, a 10 amp fuse, which feeds two gray wires to the primary pump and the ECM (voltage monitor). That red wire also feeds terminal #1 on the 2ndary fuel pump relay, whci is switched in the relay to feed an orange wire on terminal 3, to FP2 (10amp) fuse (aux fuse box), then on to that pump.
Too much detail, above?
Sounds like the primary pump or power to it has failed. I think ECM failure is a much lower probability. I surmise that pulling fuse FP2 and trying a cold start will show the #1 pump to be out, as indicated by a no start.
Ain't this fun?
Buy a Service manual, and study it. The manuals refer to a lot of fancy gear, but understanding that these are still engines, requiring fuel and spark, with easy, and basic checks like we've done for years still enable 'us' to find the problem. The ECMs merely do a more precise job of controlling the engine than the old jets, vacuum advance and such simple devices. They are not magic; just use electric sensors and controls to increase precision. They are quite reliable, with mechanical failures and/or sensor failures causing the 'brain' problems.
