Why You Need a Fuel Pressure Gauge to Speed Up Troubleshooting on Your Car

Like the human body, cars have many internal systems and functions that keep them moving along. The most obvious parallel is a human’s blood to a car’s fuel supply, each of which keeps things moving for their respective party. For both humans and cars, it’s important to keep the lifeblood at a healthy pressure. In the case of humans, we can read this through a blood pressure monitor; in the case of cars, we can keep abreast of this via a fuel pressure gauge.

If you’re driving a car, it’s important to have a fuel pressure gauge so you can keep your eye on how the fuel pressure is faring. Learn why it’s so important in this blog post.

Do I Need a Fuel Pressure Gauge?

If you want the short answer to this question: yes. If you want the longer answer to this question, keep reading. As established, the fuel pressure gauge measures the pressure of the petrol as it enters the engine. It does this to assess petrol quality and determine whether the fuel at hand can fuel the engine as needed. Can you drive with low fuel pressure? We would strongly advise against that. If the fuel pressure is too low, the engine will underperform and most likely sustain damage.

Although drivers should use a pressure gauge on an ongoing basis, it’s particularly crucial to monitor fuel pressure if you’ve just modified your engine or fuel system in any way. Moreover, a fuel pressure gauge will give that reassurance that you’re getting the best performance from your car.

What Are the Symptoms of Low Fuel Pressure?

If you’ve ever experienced low blood pressure, you may be familiar with symptoms such as lightheadedness, dizziness, blurred vision or nausea. Similarly, if your car has low fuel pressure, it may let you know via physical signs. Of course, cars cannot communicate dysfunction to us ahead of time—which is another reason a fuel gauge is so important—so if your car is exhibiting any of the following, it’s almost definitely time to stop and check in.

Performance Issues

If your engine is underperforming, you may notice more frequent stalls, more difficulty starting and an uneven running capacity.

Your Check Engine Light Is On

If this light is on, don’t ignore it. This engine malfunction could well be low fuel pressure.

Your Tailpipe Is Giving Off Black Smoke

If you ‘push the engine and pull the choke’, taking off in ‘a cloud of smoke’, your car is burning too much fuel. Get that cloud of black back to a cumulus of off-white and you’ll be golden.

Your Engine Makes Sounds That Backfire

If your engine is popping or making noises akin to gunfire, that’s a sign it’s backfiring. Coupled with power or motion loss, this diagnosis is almost surefire.

Cranking That Ultimately Ends in False Starts

If your engine won’t turn over when you try to start it, you’re probably dealing with low fuel pressure.

Unresponsive Throttle

If there is a delay or lack of response when you go to hit the throttle, low fuel pressure may well be the issue.

What Can Cause Low Fuel Pressure?

Now we know the signs, it’s time to examine the causes. What can cause low fuel pressure? Oftentimes, the fuel pressure regulator, engine and exhaust system can be to blame. Let’s take a closer look.

Engine Malfunction

The engine and fuel pressure regulator work together. If the engine is not receiving the right portion of fuel and air from the regulator, it won’t run smoothly and may even misfire.

Unburnt Petrol Burning in the Exhaust System

Backfiring is a surefire sign of petrol burning in the exhaust system. A malfunctioning fuel pressure regulator is not necessarily the culprit here, but it’s a possibility. If this is the case, it could be allowing excess petrol into the combustion chamber—which is a major fire hazard for your exhaust pipes.

Fuel Filter That Ain’t Filtering

If you haven’t changed your fuel filter in a while, get onto that. If your fuel filter is clogged, it cannot purify the fuel as it enters the engine, and this can lead to low fuel pressure.

Fuel Pump That Ain’t Pumping

Likely the most common cause of low fuel pressure, a slow or internally damaged fuel pump simply can’t push enough fuel into the engine. You know how this is going to end.

Fuel Pressure Regulator That Ain’t Regulating

If fuel is a car’s blood, then a fuel pressure regulator is its heart. If this stops working, your car will be prone to stalling, false starts and uneven driving. If the fuel pressure regulator is compromised, it will push either too much or too little fuel pressure into the fuel rail. Admittedly, the fuel pressure regulator is an unlikely candidate, but it’s still a suspect worth investigating.

Stuck Fuel Injector

Damaged or stuck fuel injectors can cause low fuel pressure. Keep your eyes peeled for misfire codes on a particular cylinder at the same time.

Fuel Pipeline on the Line

Fun as offroading can be, it can put fuel pipes at risk. They may be made of steel or aluminium, but they’re not made of stone—hence why if they encounter a stone, they may become compressed. Just one compressed pipeline can make for low fuel pressure.

Inaccurate Fuel Pressure Sensor

The fuel pressure sensor’s job is to feel the pressure in the fuel rail. If your fuel pressure regulator is electric, the fuel pressure sensor will control it. Basically, if your fuel pressure sensor is giving an inaccurate reading, it may tell the fuel pressure regulator to release the fuel pressure when it really shouldn’t. Low fuel pressure will be the natural consequence of this.

Get Fuel Pressure Gauges at VPW

Now you’re up to speed on fuel pressure, it’s time to invest in a gauge, if you haven’t got an accurate one already. In the interests of safety and performance monitoring—especially if you’ve modified your engine or fuel system lately—having a pressure gauge with an accurate reading is so important. At VPW, we have fuel pressure gauges galore from which to choose. Find your fit in our fuel gauge collection today!