Hello. This is my first time on this site. I have a question. I have a 2017 f150 XLT, 3.5 eco boost. When I start the truck, after it’s been sitting a while, I get a rattle noise that last about a second or two. I have no idea what it is. I can’t take it anywhere, because it only does it after sitting. Has anyone else had this experience. It doesn’t affect the performance of the truck. I just know that it didn’t used to do it. I have 108,000. It’s been doing it for a few years. Any info would be greatly appreciated.

 

Do a search because there must be 50 threads all about this issue. All I can say eventually it will lead to very serious engine problems imo.

 

You can read a lot about cam phaser issues, TSBs, engine flashes, etc but remember most of those threads are reporting rattles that sound like a diesel engine running and either real (not annoyances), or real perceived problems. My '17 3.5eb has a brief light rattle from cold start and has since I bought it CPO in '21. I notice it more after an extended number of days w/o being started. Pickup now has 68k+ on it; and still has a very brief light rattle at cold start up. Again, its a very light rattle and doesn't last long. I discussed it with the service manager couple years ago and he wasn't concerned but he did note it in my files and inspected under the TSB for the record. I just don't think the sound I hear is same as most of the phaser complaints.

 

Unfortunately you’re another name added to the cam phaser casualty list, of which the list is millions of engines long.

As someone said above, there are endless threads here about the issue. Just do a search and you’ll be blown away. I’m pretty much convinced almost every single 3.5 from our generation of truck has phaser issues, or will have phaser issues at some point. Ford should be held criminally responsible with how poorly they’ve handled it.

I had to do a motor replacement because of damage caused by the phasers on my vehicle, so I may be a little more biased than others on the issue. Most people just deal with a rattle and that’s it. I was one of the unlucky ones that dealt with catastrophic damage right after my warranty went out.

 

When you start truck. Hold gas pedal to the floor while cranking. engine will turn and slow rpm prime oil system once your oil gauge shows pressure release pedal engine will start no rattle unless you waited too long and your phasers are totally done for.

 

Has anyone added a prime pump for the oil system? Seems like if you could find a pump that could put out 15-20 psi oil pressure that activates on start. I suspect you could add a time delay to ignition signal so the pump has a few seconds to prime the system, then signal to start, all on push button start or key. I have a 2018 F150 Lariat, and have had Phasers replaced under warranty. Unfortunately, the dealer installed original OEM phasers and not the updated version. Pisses me off that they would do that as the new version was available at the time, but it was under warranty, nearing the end of warranty when they did it, so I suspect they were simply using up old stock knowing they wouldn't have to do it again under warranty. Sneaky and pretty chitty thing to do, but no way to prove that was their intent. I wasn't aware of the grand scheme of the issue at the time, so didn't know to ask or tell the dealership to make sure they installed the new version. Now I have an out of warranty truck that has again just started the dreaded rattle. If early oil pressure solves the issue, I am thinking of doing just that and adding a pre-oiling system to pressurize the oil system before startup. I have never used Forscan and don't currently have it, but suspect the delay can be programmed into the start sequence along with activation of the oil pressurization system prior to start signal. Might be something we can engineer and ultimately be an inexpensive fix early in the phaser rattle cycle preventing the catastrophic damage some have endured. I'll be looking into it, and if I find the parts I need will likely start my own thread on it. Just a thought.
EDIT: On second though, just a delay on activation of the fuel injectors or possibly coils would do the same and use the engine oil pump to pressurize the system, similar to holding the pedal down during start. I always forget to do it, so need something automatic that happens every time. Heck, I suspect you could program ignition to occur only after oil pressure reaches a certain point. I suspect my Corvette Z06 does this exact thing as it has a dry sump oil system, and it usually takes a few seconds of cranking before it fires. No codes, runs perfect, so I suspect it is programmed into the system to prevent fire without oil in the engine. Might be wrong, but I have to think this would be easy to program. Anyone have any thoughts on it?