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2020 QX60 - Cranks but Won't Start - No Fuel Pressure?

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Jennifer H. · rep 0 · May 22, 5:02 AM · 1 replies · solved · Question

Vehicle: 2020 Infiniti QX60 Luxe

Hello everyone,

I'm having a major issue with my 2020 Infiniti QX60. This morning, it just cranks and cranks but won't fire up. It sounds like it's trying, but there's no ignition. I don't hear the usual fuel pump prime sound when I turn the key to the ON position.

I checked the battery, and it seems fine; the starter motor is definitely engaging. I also checked the fuel pump fuse and relay, both appear good. I tried swapping the fuel pump relay with another identical one from the fuse box, but no luck.

Could this be a bad fuel pump, or is there something else I should be checking? Are there any common sensor failures on these QX60s that would prevent starting but still allow cranking? No Check Engine Light is on currently.

✓ Accepted solution

ClearTheCode Admin

ClearTheCode Team · rep 0 · May 22, 5:02 AM

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ClearTheCode admin answer:

A crank-no-start condition on your 2020 Infiniti QX60, especially with no audible fuel pump prime, strongly suggests a fuel delivery issue. Here's a diagnostic approach:

  1. Confirm Fuel Pump Operation:

    • Cause: The most direct cause of no fuel prime sound is a faulty fuel pump or a lack of power to it.
    • Action: With the ignition on, try tapping the bottom of the fuel tank (if accessible) to see if it temporarily jolts a stuck pump. A more definitive test involves checking for voltage at the fuel pump connector while someone attempts to crank the engine. If there's voltage but no pump operation, the pump is likely bad. If no voltage, the issue is upstream (wiring, relay, fuse, or control module).

  2. Check for Immobilizer System Issues:

    • Cause: The Infiniti Vehicle Immobilizer System (IVIS) can prevent starting if it doesn't recognize the key. While it usually prevents cranking altogether, some systems might allow cranking but cut fuel or spark.
    • Action: Look for a security light on the dashboard (often a key icon or 'SECURITY'). If it's flashing rapidly or staying on, it indicates an immobilizer issue. Try a different key if you have one.

  3. Crankshaft Position Sensor (CKP) or Camshaft Position Sensor (CMP):

    • Cause: These sensors are crucial for the engine control unit (ECU) to determine engine speed and piston position, which is necessary for timing fuel injection and spark. A faulty sensor can lead to a crank-no-start condition, even without a CEL initially.
    • Action: While no CEL is on, a pending code might exist. Use an OBD-II scanner to check for any pending or historical codes, specifically P0335 (CKP) or P0340/P0345 (CMP). Monitoring RPM during cranking with a scanner can also indicate if the ECU is receiving a signal from the CKP sensor.

  4. Spark Check:

    • Cause: Even if fuel is delivered, a lack of spark will prevent the engine from starting. This could be due to ignition coils, spark plugs, or a primary ignition system fault.
    • Action: Remove one spark plug, reattach its coil, and ground the plug to a metal part of the engine. Have someone crank the engine and observe for a strong, blue spark. Exercise caution during this test.

When to See a Shop: If you've confirmed power to the fuel pump and it's not operating, or if you suspect an immobilizer issue, or if you're not comfortable with electrical diagnostics or spark testing, it's best to have your QX60 towed to an Infiniti dealership or a reputable independent shop. Diagnosing no-start conditions can be complex and often requires specialized tools.

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