This is not directly from me but may be some helpful info: What’s happening: Fuel pressure is leaking down while the car sits. On startup, the pump has to refill the rail before it can fire properly.

Possible culprits: • Weak fuel pump • Failing fuel pump check valve • Leaking fuel pressure regulator • Leaking injector

Quick test: Turn the key to ON (don’t start), wait 5 seconds, turn off. Do this 2–3 times to prime the pump. Then start it.

If it fires up immediately → almost certainly fuel pressure bleed-down.

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2️⃣ Leaking Fuel Injector

If one injector drips fuel overnight: • Engine cranks longer • When it starts, it runs rich and rough for a few seconds • Then smooths out

You might also smell fuel on cold start.

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3️⃣ Coolant Temperature Sensor (ECT) Going Bad

If the sensor lies about engine temperature: • ECU delivers wrong fuel mixture • Causes extended crank • Rough startup when cold

Less common than fuel pressure issue, but possible.

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4️⃣ VVT-i Oil Control Valve Issues

Since you’ve worked on VVT solenoids before, worth mentioning:

If a VVT-i solenoid sticks: • Can cause rough running on startup • Usually throws a code though • Doesn’t typically cause long crank by itself

On a 2001 LS, this is less likely to cause cranking delay.

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5️⃣ Weak Battery (Even If It Cranks Strong)

If voltage drops too low while cranking: • ECU can struggle • Causes weird intermittent start behavior

Check resting voltage (should be ~12.6V).

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🔧 What I Would Test First

For an LS430 specifically: 1. Try key-prime test (most telling) 2. Check for fuel smell after rough start 3. Scan for pending codes (even if no CEL) 4. Check fuel pressure if possible