I have a 2004 Ram 1500 with a 4.7. I keep getting a dtc p0340. I have checked the wiring, all is good. Replaced the cam and crank sensors. I have replaced the ECM that was programed to my Vin number. Still getting the p0340 code. What I am missing

 

Welcome to DF! Moving this to Third Gen Ram section for ya.

 

Are there any symptoms, or just the light?

 

Idles rough and runs rough.

 

What brand is the cam sensor? If not factory I might consider trying original equipment?

 

I used only OEM sensors. Went and put dielectric grease in all of the connections.

 

Hmm. So you have 2 different ecms grumbling about cam sensor signal. And that's 2 different cam sensors.
Just some ideas. Maybe check resistance in cam sensor wires from sensor to ecm? With battery disconnected of course.
Possible internal engine fault.? I'm not familiar with 4.7 front timing area. How does the sensor get a signal. Is there a tone ring on the camshaft? Is engine running so poorly that the cam is out of time indicating a main timing issue?

 

You probably already know this, but I'll mention it just in case. Dielectric grease is not conductive, so if you put it directly on the pins themselves that could result in a poor connection and should be cleaned off with some electronics cleaner.

 

I liberally apply dielectric grease on all my connections, including the pins and plastic plugs. The grease doesn't prevent metal contact as it's light enough to be forced out of the way on any type of pressure connection. It repels moisture, keeps the contacts clean and easy to pull. It's also good for rubber (it's silicone). I can't thing of any car related connection where using it would be an issue. It actually reduces connection issues by preventing any sort of building or corrosion on the surfaces.

 

Sure, I use it too, although I tend to put it around the seal of the connection and not directly on the pins. But sometimes it gets on pins and that's usually ok, so I don't doubt your success with it. But it sounded like the OP added dielectric grease to connections with new sensors as a troubleshooting step to make a better connection (maybe I misinterpreted the post). But if you don't have a good connection to begin with, then dielectric grease won't make it better.