2004 f150 5.4l 3v. 147000 miles. Driving down the road today and started to hear a loud tick. Started to shutter real bad so I pulled over and shut it off. Wouldnt restart and threw a p0340 code. Had to get my buddy to tow me home. Replaced the cam position sensor on bank one, left the batt cable off for a while, tried starting it and it wants to start but wont. Havent checked to see if its thrown more codes since the new sensor, but whats the most logical next step? Im thinking its cam phasers. I guess at 147k miles its my turn! Ive searched the other posts but didnt come up with a lot of info.

 

Just checked for any additional codes. NO Codes, reader says "Pass". Thinking this is going to get expensive real quick.

 

Well, you're right at the mileage where the timing chain tensioners will fail. Tensioners have an o ring molded into the body to seal the oil pressure. When the o ring fails, you lose oil pressure to the chain which makes the chain go slack. You also lose the oil pressure which feeds the phasers causing it to go full retarded (-30degrees) this may be why it wont start. You would need to replace the tensioners and I would also recommend replacing all four chain guides. Sorry for the bad news. I can fix it, but I don't think you want to bring it to Virginia.

 

well, that's not all bad news, I guess. I'll probably do it myself but I just got it towed to the stealership for a diagnosis. Hopefully it's nothing more than that. I have no problem digging into the motor, so I guess I'll wait and see what it is. Thanks.

 

was just at the dealer picking up some things from my truck. Talked to the tech and he was perplexed. It's not the cam phasers or vct solenoids, or tensioners. 3 cylinders in the motor have lost compression, but that's not what's confusing him. What's confusing him is that it should still start, which makes sense because when the 5.4 goes into safe mode, it only runs on 4 cylinders at a time. So, this could be bigger than originally thought. FUN!

 

I was quoted $1900 to $2700 to change the phaseres with labour !!!WTF

 

i thought that the phasers are locked out on startup? There is a pin that prevents them from moving off full advanced until certain temp/pressure.

not completely sure but thought i would ask.

 

yea when mine go out, i thought about putting that 1900-2700 as a down payment on a different brand, but i don't want to own an obama mobile

 

just got the call from the stealership. They said that I have only lost compression on the #8 cylinder. They "think" that the timing may have jumped. If I have them dig into the motor to see if this is the problem, it's going to be about $800. They said that once they get there, I could need a new motor. They quoted me at $7400 to do a new motor right from the get go. If I have them dig into it and then end up needing a new motor, it will be the $800 on top of the $7400 = $8200. My concern is that a valve may have kissed a piston if the timing jumped. Also, I'm trying to grasp why no other cylinders on that bank have lost compression if the timing jumped. Why am I paying a diagnosis fee if they can only speculate on whats wrong? I don't know... I'm thinking about buying a $1000 beater car and slowly working on the motor myself. Not new to motor building at all, but this would be my first ford motor build. any thoughts?

 

If it still runs, go pick it up and pay them the diagnostic fee. Then go find a good used engine.

 

no, it won't start. I was thinking about that too, (car-part.com) but with all the problems these motors have, I'm too hesitant to buy a used motor.

 

If you have a cylinder with no compression, a used motor is going to be better than what you have.