Im looking at a friends truck trying to figure out what is going on with it. Its a 2004 F150 5.4L 3 Valve. Heres the background, he had someone replace the timing chains, phasers, tensioners, guides, VCT solenoids and new Cam Position sensors a few months ago and has had an issue with it since the work was performed. he doesnt want to take it back in fear the guy might screw something else up. The issue is when he is coming to a stop, the truck will drop idle to 500rpm or below which causes oil pressure to drop and the truck makes a knocking noise and wants to stall, if you blip the throttle it will idle back up to 600rpm or so and the knocking goes away. im assuming when the idle drops the tensioners are not getting enough oil pressure to keep the chains tight and timing is going out of whack. I have attached a quick 30 second log file where I was able to reproduce the problem, you will see the log starts with me going 19mph and slowing to a stop and for a few seconds it idles normal around 650-660 then the idle drops and around the 6:09:26 mark you will see CAM ANGLE ERROR(Passenger Bank) drop to -39 degrees and CAM ANGLE 2 ERROR(Driver Bank) stays at 0 degrees. The knocking noise definitely is coming from down low on passenger bank front cover area. Am i correct in assuming something is wrong with the way this guy timed this motor? A few teeth off maybe on the passenger side? If you look in the beginning of the log you will even see the cam angle error is consistently -4 or so when cam angle error 2 stays around 0. Im trying to help him out, hes in the military and doesnt have time to mess with the truck much. Hoping someone here may be able to shed some light on this. I appreciate any help.
P.S. I hooked up a manual oil pressure gauge and the truck idles at a solid 35-40psi, so i dont think its oil pressure related, whatever is causing the drop in idle is causing the rpms to go so low the pressure is around 25psi at 500rpm, which is to be expected.
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