Here are some common diagnostic mistakes that can cost you time, money and frustration. 1. Replacing without Diagnosing - Assuming that the fuel pump is the cause of a no start situation is the wrong way to start a diagnosis. Just because your neighbor's car had a similar problem caused by a faulty fuel pump does not mean the same for you. There are thousands of components on a vehicle that must all work in unison for proper operation. 2. Not Enough Juice - Just because you can hear the fuel pump running does not mean the pump is receiving proper voltage. Low voltage or poor ground can cause low pressure and flow. If the pressure is low at the rail, be sure to check the voltage at the pump to make sure it is within a 0.5 volt of the battery. Also make sure the battery is fully charged as this will affect the fuel pump as well as all other systems.
展开▼
