§ 03 · Diagnostics › Engine › Crank / No-Start
Cranks But Won't Start — Interactive Decision Tree
Astro & Safari · symptom-first · one question at a time
Safety first — fuel, ignition, and moving parts.
- Relieve fuel-system pressure before opening any fuel line or Schrader connection. Wear eye protection.
- Never lay a spark-plug wire against the block to check for spark — use an inline spark tester.
- Keep hands, hair, and clothing clear of belts, the fan, and the AWD front driveshaft while cranking or running.
- Use only approved starting fluid, one brief burst, air intake reinstalled, extinguisher within reach. Never on a flooded engine.
- This tool guides testing — it never tells you to replace a part before a confirming test.
1. Cranking
Does the engine crank at normal speed?
Normal cranking is a steady, brisk rotation you'd expect from a healthy battery and starter. Slow, uneven, or nothing-happens is not normal.
Structured record for your rig & future community aggregation
Saved to this device only. Kept anonymised — no personal identifiers are collected. Future release will let you contribute this as a repair report to the Atlas community pool.
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CSFI-era flooding pattern with a spider/poppet history.
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Reference for CKP, ICM, injector, Passlock, and start circuits.
- All Diagnostics →
Return to the fault library.
- Atlas Academy — testing procedures →
Voltage-drop, compression, fuel-pressure basics.
- Ask Axel for follow-up →
Grounded planning copilot with citations.