After doing the dreaded cam phaser/timing repairs on my '04 5.4, the truck cranks and starts great. I drove it 15 or 20 minutes the other day, and all seemed good. Then it began trying to stall and felt like it was missing under load. I'm getting the usual "too lean" and "over retard" codes on one bank. I just cant believe it's actually the timing based on how well it was running before that point.

Anyone have any ideas what could cause this, other than phasers or timing? I do have a couple of broken valve cover bolts on one side. Could this be causing a vacuum leak, and in turn causing the problem? Also, the catalytic converters were bad. I hollowed out the front two and cut out the back two. Right now, the exhaust is wide open behind the front cats. Could this be the problem?

 

Did you replace the VCT solenoids? If you did, did you get the super cheap ones from Ebay for $30 a pair or did you get the decent Doorman solenoids for $60 a piece or the Ford oem solenoids? In any case, disconnect the electrical connectors for both solenoids at the front of each valve cover and then see how it runs. When I did a rebuild on my engine, I went with the super cheap VCT solenoids from Ebay and the truck ran great for about a hundred miles or so and then ran awful, trying to die and then dying at idle popping the same codes. What had happened was that the cheap solenoid had shorted to ground and caused the solenoid to stay 100% open which caused full cam phasing at idle which caused the engine to run very rough and then stall. The VCT solenoid is a pulse width modulated and ground side switched device by the PCM and has constant 12v power when key is on.


The hollowed out catalytic converters are not causing this problem.

 

I did not get the super cheap ones on Ebay, but I did get the semi-cheap ones on Amazon....

 

Have you tried disconnecting the VCT solenoids?