08 F150 just had full cam phaser replacement done also new plugs, front level kit and cut muffler off and ran a pipe. Since Iv got it back the check engine light is on now. the low oil pressure light flashes for a second when starting which it did prior to cam phaser but then stopped up until recently it started again. My gas mileage has went from 13-15mpg to like 10-12? Any ideas?

 

I just did my cam phasers in my 06 truck, but I also did all the guides, tensioners timing chain , sprocket phasers, solenoids and of course gaskets along with a new oil pump, I figured I am going in their once but it wont be twice..lol

I never noticed this issue on any of my trucks but I would guess that if the sending unit just doesnt pick up the signal that it see's oil pressure off the initial start , but then picks it up right away. I doubt that your sending unit is on the fritz or I am sure you would hear it in the engine if you werent getting any oil pressure..

I really wouldnt judge this by the oil gauge in the dash, You could get the folks that did your truck to have a look at why the gauge is flickering and asking them to check the oil pressure or you could install a gauge and run it in to the truck, or use something like the scangauge to do some live monitoring ....not sure if the scan gauge would have a setting for this, maybe one of the other fellas can chime in on that.

When you did your lift did you put bigger tires on by chance or any kind of a different air cleaner?

I am just wondering if that may be the cause of your MPG drop. Of course if you were doing any towing or doing a lot of ascending that could be a factor same if your were driving in a lot of wind or your were using the heater a little more. Your tires all inflated to the proper inflation? If tires pressures are all over the map that will definetly drag down the MPG's somewhat

How long have you been seeing the MPG drop

 

Thanks for the reply. Yea I also had all the good stuff done on top of the cam phaser job. Tires are all inflated to spec, they are about a year old and no mileage change when I put them on- they aren't much bigger then stock. As far as the leveling kit I don't think 2 inches would drop mpg 2-3. Yea I need to get ahold of the shop. I'm just worried it's something else. Ugh didn't want to but the $2,800 into it in the first place but didn't have much choice when owe $15 and truck blue books at $11-13. Plus knew even if I wanted to trade no one would knowing it needed phaser job and plugs

 

It could be they missed something but I dont suspect that is the case, but I doubt they would have much of an issue with you bringing it in for them to have a look at.. Well if your hanging onto the truck for a while yet you should get a lot of good mileage out of it

My 06 F250 5.4 that I just did has 199k on the clock now and the phaser issue developed just a bit ago. I could have just sold it as it was, but decided I would fix it and do everything under there that needed to be done. Parts arent that bad its just the labor that hits ya in the wallet.

There are guys here with 5.4 engines with over 500k on them. My 02 5.4 has 209k on it and has been all maintenance items no major repairs. My 2008 5.4 has 299k on it and over 9999 engine hours ( apparently the hour meter cant go past 9999 ) and it has been a solid truck.

You'll have to update what the shop tells you when you hear back from them, be interesting to see what they find out, lets just hope its something simple

 

bad gas mileage?
1. you took off your muffler you lost back pressure just putting a piece of pipe back on to replace a muffler is not going to bring back pressure back.
2. you raised your truck the aerodynamics are even worse than what it was before the truck is having to push harder through the air because it now sits 2 inches higher more turbulent air under the truck which creates drag.
3. you have larger than stock tires on your truck it does not matter that they are a size bigger or 5 sizes bigger than stock the truck has more weight to turn.
4. we are all guilty of this but after you did your exhaust you could be on the throttle a bit more to hear the exhaust or trying to get the truck into that sweet spot where the exhaust sounds good. i did that alot and it was hard to break myslef of doing and my wife did it and it was hard to make her stop doing it. its just the sound we like to hear