runs rough, no check engine light, had tune up, changed fuel & air filter
If a fuel pump is going out will the check engine light come on? on 2003 Ford F-150
Possibly not. However, a fuel pressure test is the best way to determine fuel pump performance. Sometimes the pump will work enough to keep the vehicle running. Test it at cold and normal temps although they are more common to fail at normal to warm temps.
Thank for replying, turns out I had a dirty injector.