Intermittent not starting issue?

2009 FORD FOCUS
92,000 MILES • 4 CYL • 2WD • AUTOMATIC
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RWEIGLE71
  • MEMBER
  • 2 POSTS
Sometimes it starts right up, other times I have to crank a few times and starts, other times I have to jump then runs great. Have had battery and starter replaced. This happens when temperature is lower.
Apr 3, 2023 at 10:59 AM
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JACOBANDNICKOLAS
  • Experienced Mechanic
  • 110,240 POSTS
Hi,

Based on your description, it could be related to a failing coolant temperature sensor. If it isn't sending an accurate signal to the PCM, for example, the outside temperature is 50 degrees F and the sensor says it is -40 degrees, it will cause the fuel mixture to be off. That can cause a hard start or no start.

When this happens, do you ever notice any gray or dark smoke from the exhaust? Have you ever noticed a strong fuel smell when it finally starts?

Also, does the check engine lamp stay on when the engine is running? And do you have a live data scanner?

Sorry for so many questions. If you do have a live data scan tool and the temperature is colder outside, see what the ECT is signaling as the coolant temperature before starting it. It should be the same or very close to the outside temperature.

Let me know. Also, let me know if it runs normally once it starts.

Take care,

joe
Apr 3, 2023 at 12:13 PM
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RWEIGLE71
  • MEMBER
  • 2 POSTS
Thank you for your reply. This is a car I am considering buying, so the only question I can answer is, yes it does run just fine once it's started. The current owner took it to a mechanic and was told possibly the ignition needs replaced or it could be a fuse.
Apr 3, 2023 at 11:14 PM
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JACOBANDNICKOLAS
  • Experienced Mechanic
  • 110,240 POSTS
Hi,

Okay, they really didn't provide anything helpful. The ignition has several different components to work. And a fuse doesn't fix itself after it fails.

I would recommend having the can-bus scanned. This will retrieve codes regardless of the modules storing them.

Here is a link that shows how it is done:

https://www.2carpros.com/articles/can-scan-controller-area-network-easy

I realize it isn't your vehicle, but I would recommend having the present owner have the computer scanned to see if there are any codes stored. This could be something simple or it could indicate a possible internal engine issue.

Let me know if that is something they would have done. If they do, let me know what codes are found.

Take care,

Joe
Apr 4, 2023 at 12:19 PM
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