Help please I have a 06 f150 5.4 3v with 100000 miles, same issue of running bad and dying when warm took to shop they replaced cam sensors, phasers, timing chains, guides, tensioners and now say it has low oil pressure when it warms up but good when cold starts, ALSO 3 months ago I has all new cops and plugs put in and 2 months ago replaced a catalic converter bc was clogged. They dealer is now saying needs a new motor for 6000.00 ?? I don't get it, after they replaced cat converter 2 months ago truck ran like new, was great then drove to work and when got of highway and came to a stop it died, started back up and drove to work no issue, when I drove home from work same thing , it ran fine on highway when got off and came to stop died, took to dealer and now I need a new motor, Please help I think the 22 yr old service writer at the dealership is full of s&)t any help or direction would be much appreciated, I've read some post and there's seems to a lot of really knowledgable members here ......please help I don't know what to check next. Thanks in advance for your time

 

I know its been a few months, but did you ever get your engine figured out? I too am having problems (rough idle, lack of power, poor gas mileage. The thing is a dog to drive. No problem with stalling though). I have replaced phasers, vct solenoids, chains, guides, tensioners, lash adjusters, plugs, COPs (motorcraft), catalytic converters. Throttle body and MAF have been cleaned, new fuel filter, motorcraft oil filter used. Also did compression check. Checked good. No vaccum leaks (pretty sure). No CELs.

I have a slight tick when at op temp, and I can not for the life of me pin point it. I have probed around that engine everywhere. I will say the tick sounds loudest when I put my head down under the front of the truck.

After reading up a bit more on the oil pressure problems these 3v have, my next plan of action is to get a oil pressure gauge hooked up, run some engine cleaner, and pull the oil pan off to inspect the pan and pick up tube.

 

On the same subject. Bought a 2005 f150 a while ago that had not been maintained very well. Changed out cam phasers and tensioners; discovered the tensioner on the drivers side was collapsed and not working, causing the “diesel” sound on that side. Plugs are new, timing is perfect, and it runs really well most of the time. Only problem is now once in a while when I’m slowed down to pull into a parking place, and every time I back in my driveway, at low RPM’s it will rattle loudly and cut out. Sounds like the tensioners are not charged with oil at that point, leading to the timing chain slapping around for just that second or two before it dies. If i pop it in neutral and rev it up the noise quits and it runs fine again. Same if it dies and I fire it up again. Oil pressure gauge reads full pressure the whole time. Does anyone know where the oil pressure sensor reads from, so I can trace this down? I’m hoping I just have a sludge issue that I need to do a couple more engine flushes to fix. Any ideas?

 

Oil pressure gauge is an idiot gauge. It sits in the middle till the pressure drops to about 7 psi.

 

Hi All, has anyone solved this issue. I'm having similar issues with my 07 king ranch 5.4l and I have replaced plugs and coils, timing chain kit, oil pump and fuel filters. It still runs rough once it has warmed up. Someone mentioned the oil pan screen which seems to be clean. Anything?

 

Did you use motorcraft parts? The roller rockers wear out on those engines. But you should hear some valve clicking if they are badly worn.