No start condition, P0118 and P0343 codes

Have you repaired the wires that were taped? The -40 is an indication that you have an open circuit. That is a default when either the sensor is open or the wiring to the control module. I attached the testing for the ECT code. Pay close attention on step 6 assuming you don't repair it in a prior step. However, I suspect you have a 5 volt reference issue.

I also included the Cam code but I would start with the ECT temperature code and see what you find. I included the wiring diagram as well. As you will see the cam sensor and ECT share a low reference wire which is spliced together. That is the 5 volt reference wire which I suspect is your issue.

Let me know and we can go from there. Thanks

Hi,

The coolant temperature sensor is the likely cause of the no start. If it is indicating -40° F, it's dumping fuel to the engine to run in extreme cold temperatures.

Now, anytime I have had this happen, the sensor was bad. However, you indicated the sensor was replaced. So, we need to check it to determine if the sensor is bad or there is excessive resistance in the wiring to it, or the plug itself.

If you look at the attached pic, it shows what the resistance should be based on temp. Before going crazy and testing it, reconfirm there is no wiring damage and the connector is tight, clean, and there is no damage to the connector.

https://www.2carpros.com/articles/how-to-use-a-voltmeter

Also, just to confirm we are referring to the same part, it is located in the crossover pipe. See pic 2

Because of the sensor's location, I hate to say it, but it will be easier to remove it for checking unless you can access it to check resistance.

The only other thing I'm concerned about is the connection at the cam sensor. You indicated it was taped. Make sure that everything is properly put back together and shielded.

To shed some light on my rational for the not running condition is simple. You have two codes. From experience, I know if the ECT is indicating -40, either the engine will not start or be running extremely rich if the ambient temp isn't as indicated. If you pull a plug after trying to start it, chances are it will be wet with fuel. Now as far as the cam sensor code, the reason I don't feel that is causing a no start condition is because the system is designed to still run in a default mode even if the crank sensor fails. The only thing that will cause a no start related to the cam sensor would be if there was no crankshaft position sensor signal. Then it wouldn't run. An easy way to check for a crank signal is simple. Using your live data scanner, see if there is an RPM signal when cranking the engine. If there isn't one, chances are the crankshaft position sensor has failed. If you can't read an RPM signal, check to see if there is spark to the plugs.

Here is a link that shows how to check for spark:

https://www.2carpros.com/articles/how-to-test-an-ignition-system

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Okay, I hope this all makes sense. Let me know what you find or if you have other questions. I'll be here.

Take care,
Joe

Yes. They will have continuity but you want to check end to end. Meaning from the module to the component. Clearly when there is a splice you will have continuity from the module to multiple sensors.

If you have 5 volts coming out of the module, you can just run a new wire to each sensor. In essence you splice in a new wire and run it directly to the sensor and replace the wire that is at the sensor. Due to this being a splice for multiple sensors you don't want to eliminate the current wiring or you will lose the 5 volt reference to the other sensors. You just want to replace the wires that have the issue. This way you don't need to do an entire harness. Does that make sense?

I need to stop using the aftermarket diagrams because they are a little misleading on these types of issues. You understand me correctly but I am wondering exactly where you found 12 volts on the tan cam wire. That doesn't sound right.

These diagrams explain what is happening a lot better. The Low Ref wiring is the 5 volt ground back to the ECM. The ECM supplies 5 volts and then supplies the ground for each sensor. Look like the MAF, Cam, and ECT are the only ones on that splice. Since that is the case, I would just create your own splice to each sensor from the ECM pin 26.

Sorry I didn't get back to you. Yes. That is progress. Based on the fact that you have proper readings means you got it. Thanks for the update. Let us know when it is all back together and you get some miles on it to confirm it but I think you are in good shape.

Also, if this is you just learning then you are far ahead of a lot of mechanics out there. Wiring is one of the hardest things for most mechanics to grasp and you just found and repaired an issue that would confuse some experienced mechanics.

Thanks

Glad to hear you got it taken care of. Make sure to come back in the future if you need anything.

Take care,
Joe