2008 5.4 Head Scratcher
2008 5.4 Head Scratcher
Greetings and thanks in advance.
I had a phaser issue in my 2008 5.4 and completely changed out phasers, lifters, risers, cam sensors, water pump, plugs, and upgraded to a high volume high flow oil pump. This all stemmed from the Camshift Position Advanced codes.
After a full makeover I am getting an instant code: P0340 and P0344 which is Camshaft Position Sensor A Circuit and Camshaft Position Sensor A Circuit Intermittent.
I have had 2 independent mechanics look at the wiring and sensors and they both have made the comment the timing is quite possibly the culprit and off a single tooth. The mechanic who did the original job defends saying in his almost 40 years that would be near impossible to mess up and I would be getting a timing code but I’m not. He believes it’s a PCM / ECM issue but no one else has brought that up and this code did not exist pre-repair.
Just curious to everyone’s thoughts if it very well could be a timing related code or if it is a PCM / ECM related issue since the truck was worked on and sat for a long time while being repaired. The original mechanic has agreed to open it back up but if the timing is correct is $400 lost. I would rather apply that to a new computer.
the truck was running great even with code originally but now has developed a bit of a roughness to the idle.
— Update —
Noticed today we can clear the code and with high RPM the codes does not come back but when at idle or a fresh start the code comes up. Thinking this could be a bad out of the box phaser on bank a.
I had a phaser issue in my 2008 5.4 and completely changed out phasers, lifters, risers, cam sensors, water pump, plugs, and upgraded to a high volume high flow oil pump. This all stemmed from the Camshift Position Advanced codes.
After a full makeover I am getting an instant code: P0340 and P0344 which is Camshaft Position Sensor A Circuit and Camshaft Position Sensor A Circuit Intermittent.
I have had 2 independent mechanics look at the wiring and sensors and they both have made the comment the timing is quite possibly the culprit and off a single tooth. The mechanic who did the original job defends saying in his almost 40 years that would be near impossible to mess up and I would be getting a timing code but I’m not. He believes it’s a PCM / ECM issue but no one else has brought that up and this code did not exist pre-repair.
Just curious to everyone’s thoughts if it very well could be a timing related code or if it is a PCM / ECM related issue since the truck was worked on and sat for a long time while being repaired. The original mechanic has agreed to open it back up but if the timing is correct is $400 lost. I would rather apply that to a new computer.
the truck was running great even with code originally but now has developed a bit of a roughness to the idle.
— Update —
Noticed today we can clear the code and with high RPM the codes does not come back but when at idle or a fresh start the code comes up. Thinking this could be a bad out of the box phaser on bank a.
Last edited by Nmartin1182; Jul 23, 2023 at 12:20 AM.


