diagnostics: confirm ICP bleed-off via --crank (peak 376 psi)

Direct on-truck measurement with the verified 1446 ICP PID: peak
cranking ICP 376 psi vs the ~500 psi firing threshold.  FICM Main min
48.0 V (healthy), battery min 10.3 V (adequate).  Diagnosis empirically
confirmed: high-pressure oil bleeds off during cranking.  376 psi is
"almost there" not zero, which fits a partial leak (IPR seat / oil rail
O-rings / partial STC crack) rather than a fully blown STC fitting.

- Capture the --crank output in crank-test-2026-06-30.txt
- Add EMPIRICAL CONFIRMATION section to diagnostics README
- Update handoff "resume at the truck" to lead with physical inspection
  (IPR -> STC -> oil rail O-rings), since the OBD-side diagnosis is done

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

handoff.md

@@ -71,6 +71,13 @@ The 6.0 needs, to fire: **good batteries → FICM ~48V → ICP ~500 psi → fuel
   bus problem. Verified PID set now in `obd_reader.py`; reasoning + sources
   in [pid-research.md](diagnostics/2026-06-29-no-start/pid-research.md).
   Added `--dash` (real-time gauges) and `--crank` (no-start monitor).
+- **2026-06-30 ICP crank test:** ran `--crank` on the truck — **peak ICP
+  376 psi, below the 500 psi firing threshold**. Direct empirical
+  confirmation of the high-pressure oil bleed hypothesis. FICM min 48.0 V
+  (healthy), battery min 10.3 V (adequate). Output captured in
+  [crank-test-2026-06-30.txt](diagnostics/2026-06-29-no-start/crank-test-2026-06-30.txt).
+  Next: physical inspection (IPR valve first, then STC fitting, then
+  oil rail O-rings).
 - Pushed to `git.jpaul.io/justin/ford-obd`, branch `main`.
 
 ## To resume with Claude from the cab
@@ -80,22 +87,28 @@ no-crank, hot vs. cold, what changed before it died, and FICM/ICP readings if yo
 
 ## To resume at the truck (2026-06-30 state)
 
-The diagnosis stands: high-pressure oil (ICP) bleeds off during cranking;
-HPOP outruns the leak once running. The toolchain can now confirm this
-directly from the OBD port. Top actions, in order:
+The diagnosis is now **empirically confirmed** — `--crank` measured peak
+ICP 376 psi (need ~500 psi to fire). High-pressure oil bleeds off during
+cranking; HPOP outruns the leak once running. The 376 psi reading suggests
+a **partial** leak rather than a fully blown STC fitting. Physical
+inspection, cheap-and-easy first:
 
-1. **`python obd_reader.py --crank`** during a short crank. A healthy 6.0
-   builds ~500+ psi ICP in 1–2 seconds. If ours stalls below 500 psi or
-   builds very slowly, that confirms the bleed-off and is the smoking gun.
-2. **Probe the FICM PIDs that were outside the scan window** to validate
-   the documented `09xx` family on this truck:
-   - `python obd_reader.py --pid 09D0` (FICM Main, expect ~48V)
-   - `--pid 09CF` (Logic, ~12V), `--pid 09CE` (Vehicle V), `--pid 09CD` (Sync)
-3. **Visual under the valve covers + STC fitting** — the likely physical
-   source of the leak. STC fitting is the #1 6.0 culprit for this pattern.
-4. **Widen the brute scan** to round out the verified set —
-   `python obd_reader.py --scan 0900-09FF --scan-log scan-09xx.txt` and
-   `--scan 1600-16FF --scan-log scan-16xx.txt`.
+1. **Pull the IPR valve** (~15 min, ~$0). Bolted into the back of the
+   HPOP, top-rear of engine under the turbo. Inspect screen for debris,
+   pintle/seat for wear, O-rings for cuts. A leaky IPR seat causes
+   exactly this "partial pressure" symptom.
+2. **STC fitting visual** — between the heads under the turbo. Look for
+   wet/oily film at the fitting joint. Ford TSB; classic 6.0 wear item.
+3. **Pull valve covers** and inspect high-pressure oil rail O-rings on
+   each head. Bigger job but common 6.0 leak path.
+4. (Once a repair is attempted, re-run `--crank` — peak ICP should jump
+   to 500+ if the fix worked.)
+
+OBD-side follow-ups (lower priority now that we have the answer):
+- Probe the FICM 09xx family: `--pid 09D0` (Main, ~48V), `--pid 09CF`
+  (Logic, ~12V), `--pid 09CE` (Vehicle V), `--pid 09CD` (Sync).
+- Widen brute scan: `--scan 0900-09FF --scan-log scan-09xx.txt`
+  and `--scan 1600-16FF --scan-log scan-16xx.txt`.
 
 ## Open follow-ups
 Detailed action list lives in