sudden loss of power no codes what can it be? 2003 Ford E550 6.8 10 cil.

Hi, this is Bo, an auto expert on RepairPal's Car Genius team! Sudden loss of power and shaking in your despite no error codes can be tricky. Since you've already replaced several components, consider these possibilities: Vacuum Leaks: Even small leaks can affect engine performance. Inspect vacuum hoses and intake manifold gaskets. Exhaust System: A clogged catalytic converter or restricted exhaust can lead to poor engine performance. Throttle Body: Clean the throttle body and check the throttle position sensor (TPS) for proper operation. Compression Test: Low compression in one or more cylinders can cause power loss and shaking. Given your thorough checks, it might be worthwhile to consult a mechanic who can perform more in-depth diagnostics like a fuel pressure test or cylinder balance test. Hope this helps get you back on track! If you have any other questions, please call us at 877-913-1554! We'll gladly find you a certified RepairPal shop in your area!