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Kenny Z.
Kenny Z., Ford Senior Master Tech
Category: Ford
Satisfied Customers: 5380
Experience:  Auto Trans, Drivability and Electrical Specialist
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2004 ford f 150: crew cab with 5.4L 3v motor..actuator..faulty

Customer Question

2004 ford f 150 crew cab with 5.4L 3V motor. motor "dieseled intermitently @ idle. mechanic determained VCT actuator was faulty. replaced one and cleaned the other. cam phasers checked out ok. symtoms went away except for now still does it but only when put in reverse @ idle speed. what could this be caused by??? could the other VCT actuator be faulty as well???
Submitted: 5 years ago.
Category: Ford
Expert:  Kenny Z. replied 5 years ago.

Hello and thanks for your question.




These engines are notorious for phasers and VCT solenoids sticking from oil feed problems to the cylinder heads. The bad or sticking phaser or VCT solenoid is usually the result of the problem not the root cause. Here is a list of what I check or replace on these every time I get one in with phaser noise, VCT codes, cam sensor codes or misfires caused by VCT issues. Before any disassembly the PCM data pids for VCT error correction should be monitored to confirm it is a VCT issue. If the vehicle won't run, a compression test can also verify the VCT problem.


  • Oil Pressure. Any thing under 25 at idle will cause phaser issues. Oil pressure needs to be steady and not fluctuating. If low or fluctuating suspect crankshaft thrust bearing wear. This can be verified by a simple end play check. Also if engine is sludged in the least amount there could be oil starvation to the valve train which is also very common on these and can be verified by pulling a few cam caps on each side, it will be obvious if the there is an oil supply issue to the valve train by the condition of the caps and journals.
  • VCT valve body/solenoids. Have seen many issues with solenoid plungers sticking and restrictions in valve body due to plugged or collapsed screens.
  • Timing chain tensioner gaskets blown. This will cause oil pressure bleed to the valve train and affect phaser functionality.
  • Camshaft phasers sticking due to contamination or low oil volume/delivery pressure.
  • Crankshaft endplay, I don't bother fixing the engine if endplay is over .010
  • Oil pump, I change if there was any evidence of sludge or varnishing. There are passages in the pump that clog and can cause oil starvation problems.

In short if I don't find oil pressure concerns and my cams are in good shape I usually replace the phasers, VCT bodies, oil pump and tensioners on every one of these. Ford has updated these part numbers several times with improved engineering designs.

Customer: replied 5 years ago.
are anti drainback oil filters also recommeded on these engines?
Expert:  Kenny Z. replied 5 years ago.
They are, the motorcraft filters have this feature but unfortunately I have never seen the lack of an anti drain back valve cause the issue these engines have.
Customer: replied 5 years ago.

do you recommed running sea foam through the engine before oil changes?

Expert:  Kenny Z. replied 5 years ago.

No I don't. If there is sludge present, it is going to make it worse. The passages in the vct bodies and the screens are very small as well as the cam bearing passages. Anything that breaks loose upstream of the filter can be trapped in the vct passages and screens.