(P0345) very rough Idle when sensor is plugged in?

2004 FORD F-150
200 MILES • 5.4L • 4WD • AUTOMATIC
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NICHOLAS LOPES
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I have a Camshaft position sensor Bank 2 code. When the sensor is plugged in, it runs like shit and will die. However when unplugged it runs fine with no odd noises. Just a slight loss of power at freeway speed, due to the sensor being unplugged.

I have tested and changed the sensors with known good ones and no changes. All sensors test good at 350 ohm, and when checking for shorts with moltimeter on the wire I found none.

The way I tested was checking for continuity between ground and each pin on harness, only one wire had continuity to ground, witch I assume is the ground or (-) wire.

I also checked for A/C voltage at the batery and altinator, as I heard there is issues with leaking a/c voltage with diode and alternator starting to fail, causing fals signals. However my meter didn't pick anything up and my altinator seams to be working well.



Any directions would be helpful thank you.
Sep 3, 2026 at 12:54 PM
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MECHTRIX
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These ford f150 with the 5.4 eng notoriously have issiues with the cam fazers its comon on the 2004 to 2010 models they tend to loose oil pressure in the can fazers sorry to say but this vary well could be the start of the fazer getting weak and not advancing all the way on bank 2 wich would cause the cam to retard slightly loos a bit of top end power and send the code your getting especially if its a known good cam sensor best of luck hope this helps please let us know what you find
Sep 3, 2026 at 9:44 PM
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MECHTRIX
  • ✓Experienced Mechanic
  • 529 POSTS
Id say erase the code and drive it to see if the code comes back it might not since you just recently changed the cam sensor also that code is indicating that theres a problem with trnsmitting /receiving a signal so it vary well could be one of the wires or plugs going to the ecm maybe at the pin connector /plug at the ecm id check there if you havent yet somtimes unplugging it then plugging it back in solves the problem also just to see if any of them got corroded brocken or disconnected in any way just to rule it out good luck
Sep 4, 2026 at 1:50 PM
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