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Pete, Automotive Mechanic
Category: Medium and Heavy Trucks
Satisfied Customers: 29112
Experience:  Performed various automotive repairs on several light duty and medium duty vehicles over 15 years of service.
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Starts but won't stay running, 7.4 c6500 gmc, New crank

Customer Question

Starts but won't stay running
JA: What is the complete model and serial number of your machine?
Customer: 7.4 c6500 gmc
JA: Are you fixing this yourself? What have you tried so far?
Customer: New crank sensor and cam sensor
JA: Anything else you want the equipment mechanic to know before I connect you?
Customer: Code p0342 & p0117
Submitted: 11 months ago.
Category: Medium and Heavy Trucks
Customer: replied 11 months ago.
Will low battery bring up the code p0342
Expert:  Pete replied 11 months ago.

My name is ***** ***** I am a professional here at Just Answer. I noticed that your question had not received a response and thought I would see if you still need help with this.I apologize for the delay and I hope I can still assist you with this here.My info is somewhat limited on your model here but I had seen no one else has responded and would like to see if I can help here.If at any time you feel that I cannot help with this please let me know.

If you have an issue with low voltage this can cause this fault here.It affects the electronics on the engine and the engine computer itself.If you have a low voltage issue due to a battery cable,battery or alternator issues this should be checked into and repaired first.

If more help is needed, use the reply tab to continue our conversation. If no further assistance is needed, kindly rate my service,your 5 star rating is appreciated.You can rate at any time and we can continue to work on your question as this will not close out your question.Keep in mind in some cases it can be difficult to fully diagnose or help repair your vehicle without seeing it and I work on delivering the best possible answer from what I see to work with.

Thanks Pete

Customer: replied 11 months ago.
Hi Pete we'll I understand that the owner put a new engine in it an they couldn't get it started so they called me I go check it out put it on my computer if coffee calling for a crankshaft position sensor low-voltage I change the crank sensor I change the battery I checked all connections only thing I didn't check with all the ground that's on there I'm thinking maybe is one of the grounds on the motor I even checked the computer they had computer flashed and steal it turns it starts but won't stay running
Expert:  Pete replied 11 months ago.

Is the crank code still setting?

Customer: replied 11 months ago.
Expert:  Pete replied 11 months ago.

Since this occured shortly after the engine was replaced I suspect a ground issue as well or wiring fault on the engine with wiring that was not installed properly or connected properly.I would have the wiring checked on the engine as well as the grounds from the battery to the engine block and body for any issues.

Let me know if you need anything else and feel free to rate my help here as this is how I receive credit for my time.A 5 star rating is appreciated.Thanks Pete

Customer: replied 11 months ago.
Thanks that was I thinking it is
Expert:  Pete replied 11 months ago.

Your welcome

Customer: replied 11 months ago.
Hey Pete I did everything check all the grounds and chance some of them check the power to the cam sensor and ground and still start but won't run
Expert:  Pete replied 11 months ago.

If all wiring and connections to the crank sensor are all found to be o.k. this may be timing related here then with an issue with one of the timing components causing the cam sensor code and the no start.If you have not had the timing inspected I would see if this is the cause here at all.

Let me know if you need anything else and feel free to rate my help here as this is how I receive credit for my time.Your 5 star rating is appreciated

Thanks Pete