Faulty Fuel System Parts That Keep Your Car From Starting | Phoenix Auto Repair
SYNOPSIS: Have you ever had a hard start, where the engine takes longer than usual to crank? Perhaps it starts, only to stumble and stall, or worse—it doesn't crank at all. Learn why!
Faulty Fuel System Parts That Prevent Starting
BY: Daniel Langham, Phoenix Auto Repair
If you find yourself in a situation where your vehicle won't start, you are certainly not alone! This could very well be a sign of a major starting system problem. Have you ever had a hard start, where the engine takes longer than usual to crank? Perhaps it starts, only to stumble and stall, or worse—it doesn't crank at all. These symptoms suggest possible problems occurring with your fuel system and, more specifically, fuel pressure.
Let's talk about diagnosing the problem. You have a vehicle where the engine just doesn't want to crank, or maybe it hesitates for a moment. The place to start would be looking at the fuel pressure: the fuel pump, the lines, and the filters. Taking these steps can help you identify the issue and get back on the road safely.
The first thing you should check when diagnosing a possible fuel problem is your fuel pressures. You have to have a good functioning fuel pump sending unit. To begin this test, you will need an assistant to help you out. It is a very simple procedure and doesn't take any special equipment.
Have your partner sit inside the vehicle. They should insert the key and turn it to the "on" position, but there's no need to crank the engine. What you’re trying to do here is listen for a very faint humming noise that indicates the fuel pump is operating. While they’re doing that, you will need to get safely underneath the vehicle, positioned near the fuel tank.
Stay alert; your main task is listening closely to that humming sound. If you can't hear it while you're under the vehicle, don't panic. You can use your hand or a rubber mallet to gently tap on the bottom of the fuel tank. Sometimes, this can revive a sleepy pump. If the engine starts after this, great! You’ve managed to get the vehicle going, but it’s essential to realize this typically indicates you have an issue with the fuel pump sending module. Did it turn out you need a replacement pump? Look no further than for help from our experts here at Phoenix Auto Repair!
Now that you’re beneath the vehicle, take a moment to inspect the fuel lines along the side of the frame. If your car has an external fuel filter, now would be an ideal time to examine that as well. As you visually inspect these components, pay attention to your sense of smell. It’s critical to check for any fuel vapor in the air or visible leaks, whether drips or just condensation. Any sign of a fuel leak is a red flag that requires immediate attention.
Assuming that you did hear the fuel pump working but are still experiencing issues starting the engine or if the vehicle starts but stalls out unexpectedly, it’s time to move your inspection to the fuel rail. On many vehicles, the fuel rail is somewhat exposed, making it easier for you to access. Locate the valve on the fuel rail and carefully remove the protective cover.
This next step demands precision, so take your time. You will be testing the fuel pressure by pressing down on the valve in the center, which will release any built-up pressure. Be cautious, as gasoline might spurt out when you do this. If liquid fuel comes out, that’s a positive indication that fuel is making its way up to this point in the system. However, to fully assess the situation, you need to know how much pressure you actually have.
If you have a fuel pressure gauge, now’s the time to attach it to the valve. This gauge will give you a reading of the fuel pressure. Familiarize yourself with the specifications for your specific vehicle, since acceptable fuel pressure typically ranges from 30 to 50 psi or slightly higher, depending on the application. Knowing the expected pressure is vital; if you discover that the fuel pressure is below specifications, this could very well be your problem, and the fuel pump assembly could be the culprit.
