The steps to replace a fuel pump that will not prime depend, to some extent, upon whether you have them access to the pump. If the fuel pump fails to prime, then the engine will have difficulty starting or running, as the fuel pump is critical for delivering fuel to the engine. Usually, when you turn the ignition on, the fuel pump primes and fuel is sent to the engine. But if the pump does not pump prime, then the pump itself may be faulty, or perhaps the relay or electrical contact.
An easy diagnosis is to check the fuel pump relay and fuse. If these are faulty, they may stop the pump from working. If a fuel pump relay malfunctions, if it fails electrically, the pump will not turn on. About 30% of fuel pump problems are associated with either relay or fuse failure and can be easily replaced, according to Auto Diagnostics Group. If after checking the relay and fuse the problem still shows up, the next step is to test the fuel pump itself.
Because the fuel pump is usually located inside the vehicle’s gas tank, replacing one that won’t prime requires draining and removing the tank. This process needs to be treated with care to prevent breaking the car or prevening spillage of fuel. According to a study conducted by CarTech Solutions, the average time needed for a mechanic to remove a fuel pump inside the tank ranges from 2-4 hours, depending on the specific vehicle’s make and model. To start, make certain you have the correct replacement pump, as it should be properly matched to the vehicle to perform optimally.
The following step is to remove the old pump’s fuel lines and electrical connectors. Remove the fuel pump and then you can install the new one once tank is free. Replacements of fuel pumps often cost $100 to $500 (depending on the vehicle and the type of pump). In some cases, the fuel pump assembly is made up of the fuel level sensor and other components, which may reflect in the cost.
Once the new pump has been installed, check for leaks and ensure that all connections are secure. If all is in order, turn on the key to test fire the pump. The pump should now prime and fuel should flow to the engine. If the pump still doesn’t prime, then the fuel pump control module could be to blame; that’s the electronic device that controls the operation of the pump. Fuel delivery problems caused by failing fuel pump control modules plagued John Deere on their fleet vehicles a while back. In these scenarios, swapping out the module fixed the problem and normal fuel flow was reinstated.
“If you think you can do a thing or think you can’t do a thing, you’re right,” Henry Ford has been quoted as saying. Replacing a fuel pump that refuses to prime with the right tools in hand and a keen eye for detail is a perfectly achievable project that can bring back engine performance and fuel economy.
Check Fuel Pump for Fuel Pump Replacement and Troubleshooting