Intermittent hard start with backfire

2006 PORSCHE CAYMAN
90,000 MILES • 4.0L • 6 CYL • 2WD • MANUAL
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VASSZ
  • MEMBER
  • 1 POST
Happening more and more frequent now.
cranks but won't start. after you keep trying, it backfires.
sends a p0339 code which is crank sensor.
changed it but same problem.
Oct 4, 2020 at 8:53 PM
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KASEKENNY
  • ✓Experienced Mechanic
  • 18,907 POSTS
Have you replaced the crank sensor? More then likely this is starting to fail. If not then we have a connector or wiring issue. However, due to it being intermittent this sounds like a contact issue in either the sensor or the connector.

Let's start with this and go from there.

https://www.2carpros.com/articles/symptoms-of-a-bad-crankshaft-sensor
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Oct 5, 2020 at 8:35 AM
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