Help engine rough idle and stalls out

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I have 2008 expedition last week it idled really rough and if you stepped on the gas it quit running. I got 6 codes 4 were cylinder 1-4 misfire the other 2 were P0340 and P0344. I bought a new cam shaft sensor cleared the codes and started it. Car starts perfect but after about 5 seconds it runs right then shuts off and I got about P0340. I went back to AutoZone and bought another sensor in case it was a bad one. I installed the new one same thing. So I bought another sensor and changed out both of them same result. I checked the MAF sensor and when it’s not installed the car stays running but when I step on the gas it stalls out and code P0113 pops up. I’m really hoping it’s not a timing issue because I replaced the timing chain in 2018 and it’s been driving like a champ until this. If anyone has any idea what I need to do or check next I greatly appreciate it.
 

riphip

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P0340 is CPS
P0113 is IAT....Intake Air Temp sensor. Can be loose connection

Also check any vacuum connections/hoses.
 

Psychobot90

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Going to jump on this thread instead of starting another.
I also have PO113 with the rough, idle/lean condition and rough acceleration symptoms. The code is accompanied by several misfire codes that change cylyinders. New plugs, new coils, weephole, etc. already done. to solve the problem I bought the $15 sensor and installed it, but no dice. Same codes.
Forscan shows:
upload_2020-12-30_19-39-41.png
Which is wayyy out of scope. Multimeter on the leads shows 5V reference is correct (based on battery negative), but the voltage going back to the ECM reads 33V which also out of range. Tested from battery negative to sensor wire.
This is driving me nuts...what am I doing wrong? I have a feeling the solution is obvious, but I can't see the forest through all the trees.

Here's some more Forscan data:
upload_2020-12-30_19-45-49.png

Iv'e been through this engine and I'm stumped here.
 

Psychobot90

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It sounds like a spark or timing issue to me. very hard to say without seeing it infront of me though.

SOME BACKGROUND:
The vehicle has 114K on it. I bought it about 4500 miles ago and changed out the (original) plugs and coils which had some pretty solid coking. The exhaust also had a lot of carbon buildup, so I am assuming the lean condition was not recent. after running injecter cleaner additive and premium fuel for a couple tanks, I changed the plugs and coils. I drillled the CAC at the same time to eliminate as many known issues as possible. There was still a slight misfire under load, but the conditions improved for a while. I noticed the PCV making noise at idle (fluttering) so I replaced it and the idle/misfire condition was almost completely gone. After just a day the IAT sensor code was thrown and eveything went to pot - rough idle, lean condition, misfire under load, misfire at startup, etc. etc. I have reset the PCM learned values and throttle learned values. I am at a loss.
Can somone perhaps tell me if my multimeter test results are scewed due to my own ignorance? Or are those readings likely why the code was thrown?
 
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Saundersbronco
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I found out on my vehicle I don’t have a IAT it’s built into the throttle body. So I bought a new throttle body hooked it up it ran fine then I stepped in the gas and it stopped. P0340 code came back and I found the connector was loose on the camshaft sensor. Now it runs but I step on the gas and it dies. The codes are P0340,0344 and 2 for the O2 sensor
 

riphip

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Your inside looks much cleaner than this one. Chain guides/tensioner broke & lodged in chain/cog after shutdown then went to start. Would not turn crank. You can see from the deposits that it should have had more than 2 oil changes (?) in it's 75k miles running. On a maintenance/welding truck to boot.

upload_2021-1-12_14-27-15.jpeg
 
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