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Hello and welcome! My name isCustomerand I can assist you with your question. Was the PCM replaced? If not, it might just be as simple as that. Especially if your loosing the 5 volt reference. You are going to want to check all powers and grounds going into the PCM first before replacing it. Also check to be sure that the 5 volt reference is not getting shorted out by any other sensor on that circuit.
Some other possible causes are an air or a vacuum leak, bad or dirty throttle body, MAF/MAP sensor, fuel pressure regulator and or weak fuel pump.
The sensors that share the 5 volt reference are the MAP, TPS, EGR valve and the fuel tank pressure sensor
Here is a wiring diagram of this circuit.
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Engine running the fuel pressure should be 43 to 56 psi.
This is because the air fuel ratio is way off.
Sounds good. Also, dont forget to check the fuel pressure regulator for leaks
Hello! It'sCustomerfrom just answer.
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Hello and thank you for that information. Have you checked the coolant temp sensor? How about the MAP sensor? Based on my experience, this is going to be a fuel delivery issue. Not an ignition system failure.
So are you saying that you are getting cam/crank sensor codes?
Can I get the codes stored in the computer?
Please send me your VIN
Thank you for that information. These codes indicate an issue with the crankshaft position sensors.
Hello! YES, it is same set up and yes, it can be a problem. However, this would set a code based on my experience.