P0263 and p0284 Low on power

[jonathanrayce]

97 f450 The truck keeps throwing these 2 codes even after replacing with new injectors and new CPS. The truck feels like it has a slight miss. Power is greatly reduced when hooking to a load. What could be causing this?

[okney1lz]

A short in the harness that goes from your IDM to you Valve cover connector could display these codes.

Also a damaged UVC Harness, or actual gasket, but I would imagine while installing injectors that would be ruled out.

A standard DVOM should allow you to test these things.

Or it could be the IDM.

They're notorious for getting water trapped inside.

You could try swapping out IDM's if you know someone else with the same one.

Hope this helps,

Lawrence