new motor???
 

I have a 2006 Ford F-250 Super Duty 5.4l XL.
Recently it started having a loss of power and would "chug" down then regain power. My CEL has been on for several years with the code always being a P0430 code. Had my cat checked and was informed nothing was wrong with it and no other codes where shown, to my knowledge. Now it is showing P0022, P0171, P0300, 302,305,306,307, 308, 0316, 0420 and 0430.
I was told because "20" was showing up in to many of the search results for possible problems I should just replace the motor that the cost would be about the same. I can't afford $5000.00 for a new motor and can't really afford to buy a new vehicle. One mechanic suggested the problem could be my VCT solenoid. So I replaced that to no change. I found info that suggested he could have tested that but didn't. The parts to so many not be expensive but to me it was a wasted effort. I could us some suggestions here.

With over 20 faults showing up in your scan you can expect 2 or 3 of them is your problem. I understand his explanation that he can't pin point the primary issue by investigating each issue one at a time.
So he could try CLEARING all the faults with the scanner then starting from scratch and do a LIVE SCAN.
First fault up may be the primary fault.
(That's were I would start) but there is the possibility that fault may have caused other faults
Good luck
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