Aug 13-14, 2026

Day 5 — Polarity Correction & the Cranking Voltage Discovery

8 logs analyzed · 39 minutes of logged data · 28 stall/restart events detected

The most consequential day of the project Flipping idle solenoid polarity to "default" initially looked like a regression — idle got worse, not better — but the fan-adder direction test confirmed the polarity fix itself was correct; the base idle table simply still commanded far more air than a 70 mm throttle body needed. Separately, newly-decoded SD-card logs revealed the real cause of the week's hard-starting problem: cranking voltage collapsing to 5.79 V, well below what the ECU and injectors need to operate reliably.
8
Logs this day
39m
Logged duration
958
Avg idle RPM (session-wide)
28
Stall/restart events

05Log-by-Log Breakdown

Session-wide statistics computed across each full log. These pool every idle-qualifying sample in the file, so they run higher than the narrow steady-state windows cited in the final project report — that's expected; this view shows total session variability, not just the best segment.

Start-5...IACV-Default.mlg

Idle solenoid polarity switched to 'default'. Idle got WORSE (2450-2680 RPM) — the direction was right (confirmed by later fan-adder testing) but the base idle table was still far oversized for the 70mm throttle body.

125.4s
Duration
12531
Records
124.1–188.7°F
CLT range
2685.0
RPM max
2023.0
Idle mean
753.5
Idle σ
—
VBatt (crank min)
0.0%
Fan on %
0
Stall events*
Start-7-WarmStart-CoolantBleed7.mlgLOW CRANK VOLTAGE 7.94V

Repeated stalls. Cranking voltage found collapsing to 5.79V — root cause of the multi-attempt starting problem.

524.6s
Duration
49225
Records
191.8–194.2°F
CLT range
1306.0
RPM max
633.0
Idle mean
285.8
Idle σ
7.94V
VBatt (crank min)
72.0%
Fan on %
2
Stall events*
Start-9-WarmStart-CoolantBleed9.mlgLOW CRANK VOLTAGE 0.0V

Coolant bleeding largely complete. Idle table rescale work begins in earnest.

364.1s
Duration
36396
Records
161.4–212.9°F
CLT range
3608.0
RPM max
1092.0
Idle mean
289.3
Idle σ
0.0V
VBatt (crank min)
81.0%
Fan on %
3
Stall events*
Start-12.mlgLOW CRANK VOLTAGE 0.0V

IACV physically tapped to try to free it — produced one good long stretch but inconsistent plateaus (960/1480/1550 RPM) across the same log.

712.5s
Duration
69571
Records
169.8–212.5°F
CLT range
4266.0
RPM max
1510.0
Idle mean
385.7
Idle σ
0.0V
VBatt (crank min)
91.0%
Fan on %
9
Stall events*
re_260807_074842.mlg (SD)

SD-card log, cranking sequence — engine ran fine once caught.

121.6s
Duration
5530
Records
200.9–210.9°F
CLT range
1004.0
RPM max
913.0
Idle mean
74.6
Idle σ
—
VBatt (crank min)
100.0%
Fan on %
0
Stall events*
re_260807_075055.mlg (SD)LOW CRANK VOLTAGE 5.98V

SD-card log — VBatt sagged to 5.90V during crank, failed to catch.

30.4s
Duration
1320
Records
206.9–207.8°F
CLT range
6488.0
RPM max
329.0
Idle mean
19.3
Idle σ
5.98V
VBatt (crank min)
100.0%
Fan on %
1
Stall events*
re_260807_075131.mlg (SD)LOW CRANK VOLTAGE 5.79V

SD-card log — VBatt sagged to 5.79V during crank, failed to catch.

41.9s
Duration
1890
Records
204.9–206.1°F
CLT range
762.0
RPM max
357.0
Idle mean
75.0
Idle σ
5.79V
VBatt (crank min)
100.0%
Fan on %
3
Stall events*
re_260807_075219.mlg (SD)LOW CRANK VOLTAGE 0.0V

SD-card log — eventual catch after ~45s cumulative cranking effort.

393.3s
Duration
17603
Records
199.0–212.2°F
CLT range
4144.0
RPM max
807.0
Idle mean
222.1
Idle σ
0.0V
VBatt (crank min)
100.0%
Fan on %
10
Stall events*
* On stall/restart counting Detected algorithmically as RPM dropping below 300 for a sustained period followed by a subsequent rise — a reasonable proxy for restart events, not a precise fault classifier. Treat as directionally accurate, not exact.
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Day 4