First post, so forgive me if I didn't search enough and this topic has already been addressed.

03 Concorde Limited, 3.5L. Car shows no signs of anything being wrong. Runs smooth, idles smooth, acceleration is not a problem. I "think" I've narrowed down when it cuts off. It only appears to be when braking at normal to relatively hard pressure. The car will be running along fine, a light will change faster than you expected, you step on the brakes, and the motor cuts off. Throw it in neutral, hit the key, and it cranks right up immediately. This is a very intermittent problem too, making it even more difficult to diagnose. My first guess is vacuum leak, but I haven't been able to find one.

CEL finally came on Wednesday of this week. I was right by O'Reilly so I had them scan it. It pulled 340 and 344. I did some research and found out this was related to recall J18 (incorrect voltage from the PCM to the Cam Position Sensor). I had that taken care of today, but the problem still exists.

So here I am, looking for advice from the experts!

 

Should have added this in the original post. I've done a shade tree mechanic tuneup (plugs, oil/filter, air filter) already, as well as ran some fuel system stabilizer through it (thought it may have been some bad gas).

 

if the update did not take care of it then replace the sensor for the code.

 

Codes are related to the Camshaft Sensor, as are your symptoms. Bet your cruise control is also a little funky too.. It is located at the front of the engine, drivers side of center, just under the front edge of the intake "plenum". In most cases the intake plenum needs to be at least loosened to lift slightly to remove the sensor. (3 wire plug/10mm wrench sise bolt)
OEM only is strongly recommended. Aftermarket ones tend to last only a year or so (poor quality off shore magnet) There is a paper shim on the new sensor, leave it on the new one when installed. Sets the "air gap" to the cam tone wheel and harmlessly falls off once installed.

 

Thanks for all the replies, and my apologies for coming back to this after so long, as life sometimes does, it's been kind of crazy lately. So I replaced the cam sensor last night (super easy job by the way). I did not get OEM, probably should have in retrospect and after reading more this morning. Anyway, replaced the sensor, cleared codes, all is well....for about 15 minutes. Car cut off at a stop sign, cranked right up like nothing was wrong, and was driving fine. Engine light came on again, pulling P0344. Looking for ideas from the experts here now.

 

Did you leave the paper "shim" on the new sensor ? (Correct answer should be yes.) It sets the "air gap" to the tone ring on the cam drive. If "no" your new sensor is most likely damaged.
Aftermarket sensors "iffy" at best... 30 day warranty ??

 

Yep, the paper shim was intact and I did not remove it. I will make this puzzle a little hjarder now. While driving the vehicle this afternoon, the CEL turned off, no more P0344. However, the damn car is still turning off when you stop at a light or something.

 

FWIW Crank sensor also related to this issue. If you are sure the cam sensor is OK may want to consider the crank sensor. I do not recommend random parts changing but in the case of these two sensors usually change both.
P0344-CAMSHAFT POSITION SENSOR INTERMITTENT
WHEN MONITORED
Engine running or Cranking.
SET CONDITION
When the failure counter reaches 20. One Trip Fault.
POSSIBLE CAUSES
Intermittent condition
Wiring harness inspection

• 5 volt supply circuit open or shorted to ground
• Tone wheel/pulse ring inspection
• Checking crankshaft position sensor signal with the DRBIII (R) LAB
• Camshaft position sensor
• Signal circuit open
• Signal circuit short to ground
• Signal circuit shorted to B+
• Signal circuit short to 5 volts
• PCM

 

I have read that about the crank sensor being related, glad you confirmed it though, because in my mind that was the next step. I'm like you, I hate throwing random parts at it, but with a problem like this, diagnosis is so difficult, there isn't much choice. I will update again after I've changed that out. In the meantime, if anyone has any other thoughts, all opinions and ideas are welcome.

 

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