Engine will not stay running and Cam sensor reading is zero

2009 GMC ACADIA
160,000 MILES • 3.6L • 6 CYL • 2WD • AUTOMATIC
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DAN MARTINDALE
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I've been having trouble with my vehicle starting and then immediately stalling. When i do a live scan i notice that the cam sensors are all doing counts, but it shows cam sensor RPM at zero. I think the problem may be there which is probably affecting timing.

What is the most logical cause of this? I am getting zero codes but show a very lean mixture of 29.3:1 command ratio and about a .9 equivalence ratio. Thanks for your time.
Jan 6, 2022 at 9:06 AM
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JACOBANDNICKOLAS
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Hi,

The idea that it is running lean can be the result of low fuel pressure or an engine vacuum leak. Have you checked either of those at this point?

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Also, did you check for a crankshaft positions sensor signal? That can prevent an RPM signal. However, I wouldn't even think it would start without either providing a signal.

Let me know.

Joe
Jan 6, 2022 at 5:19 PM