i have the p0171 combined with p0174. how do you check for a intake leak

Question

it is a 1998 ford f-150 and those are the codes it reads p0171 and p0174

Answer 1

Hi there,

To check for vacuum leaks do this. With the engine running, spray carb cleaner along the intake manifold and any vacuum lines you see. If you have a vacuum leak the idle speed will either increase or smooth out.