Many owners of Ford cars, trucks and SUV’s with the Triton engine (4.6L, 5.4L, and 6.8L) have experienced a rough idle along with a knocking sound at low engine speed. Many drivers describe it as sounding like a diesel engine. These symptoms have been diagnosed by different technicians as anything from a faulty oil pump, dirty oil, or a worn valvetrain to a bottom end (rod knock), piston slap, and various other things. Often the owner is told they need to spend thousands of dollars on unnecessary repairs up to and including a complete engine rebuild when in fact the real problem is much simpler and less costly to repair.
More often than not the real cause of this noise is that one or both of the cam phasers have worn out and started rattling inside the valve covers. Let’s take a look at how this part works, why it breaks, what subsequent damage can result from not getting it fixed and last but not least, how it is repaired.
What are cam phasers? Many modern engines utilize cam phasers in conjunction with variable valve timing (VVT) solenoids to modify the engine’s valve timing in order to better suit varying driving conditions and provide a wider powerband and better overall fuel economy. The cam phaser itself is basically a gear or sprocket bolted onto the end of the camshaft that allows for a varying relationship between power input (from the timing chain) and power output (to the camshaft). The engine will run more efficiently and economically at a given speed with a certain relationship between the opening and closing of the valves and the reciprocation of the pistons. This optimum relationship (valve timing) varies with engine speed and load. The cam phasers allow the valve timing to be adjusted on the fly by using engine oil pressure to hydraulically rotate the input side of the cam phaser against the output side. Over time, these components can become worn or even break and start to come apart inside your engine. One common result of driving with failed cam phasers is that the tone ring on the front of the phaser will start hitting the cam position sensor and destroy it. In extreme cases we have seen the cam phaser come apart completely and cause the engine to jump time, destroying the valvetrain and much of the top end of the engine.
What cars and trucks are affected?
4.6L engine:
- Ford Mustang GT 5005-2010
- Ford Mustang Bullitt 2008-2009
- Ford Explorer 2006-2010
- Mercury Mountaineer 2006-2010
- Ford Explorer Sport Trac 2007-2010
- Ford F-150 2009-2010
5.4L Engine:
- Ford Facom/Futura/Fairmont 2002-2007
- Ford Fairlane G220 2003-2004
- Ford LTD 2003-2007
- Ford Fairlane G8 2005-2007
- Ford F-150 2004-2010
- Ford F-250 2004-2010
- Ford F-350 2004-2010
- Ford Expedition 2005-2014
- Lincoln Navigator 2004-2014
This video shows more information about the cam phasers and how to recognize when they have failed:
[embedyt] http://www.youtube.com/watch?v=O7GcqtNTMqQ[/embedyt]
Because of the faulty design of the cam phasers themselves, there’s really no practical way to repair them. They must be replaced with new, better designed units. It is highly recommended to replace the timing chains and guides at this time, as they are known the wear prematurely in these engines as well.
What we do here at Integrity AutoWorks is disassemble the front of the engine and remove the timing cover, and replace both phasers, both timing chains, and all the guides. Since it is best to remove the timing cover in order to replace the cam phasers, the additional labor to replace the chains and guides is minimal and therefore it is a very good idea to replace all these components at once, rather than having to pay for all the labor to expose them again when they fail.
We have done lots of Ford Triton cam phaser replacements, and we do them quicker and at a lower cost than just about anyone else. Give us a call and we will give you a quick, low cost quote and schedule an appointment to get your vehicle repaired as soon as possible.