1991 Chevy Caprice Fuel Pump Fuse Location: Complete Guide to Finding and Fixing It

The fuel pump fuse on a 1991 Chevy Caprice is located in the engine compartment fuse box, on the passenger side near the firewall. It is a 15-amp fuse, labeled as position number 2 in the under-hood fuse block, and it protects the fuel pump relay, the fuel pump itself, and the engine oil pressure switch circuit. If your Caprice cranks but won't start, or if you hear no fuel pump whine when you turn the key to the ON position, the first thing to check is this fuse. Keep reading for a step-by-step guide to locating it, testing it, and troubleshooting common fuel pump issues on the 1991 Chevrolet Caprice.

Where Is the Fuel Pump Fuse on a 1991 Chevy Caprice?

The 1991 Chevrolet Caprice has two fuse boxes: one inside the cabin under the dashboard on the driver's side, and one under the hood in the engine compartment. The fuel pump fuse is not inside the car. It is located in the engine compartment fuse box.

To find the engine compartment fuse box:

  • Open the hood of your 1991 Caprice.
  • Look on the passenger side of the engine bay, toward the rear near the firewall.
  • You will see a rectangular black plastic box with a removable lid. This is the engine compartment fuse and relay center.

Inside the fuse box, the fuel pump fuse is:

  • Position: Number 2 (in the under-hood fuse block)
  • Amperage: 15 amps
  • Label: Often marked as "F/P" or "Fuel Pump" on the fuse box cover diagram

The fuse box cover should have a diagram showing which fuse is which. If the diagram is missing or worn off, the fuel pump fuse is typically the second fuse from the left in the top row or a clearly marked position near the fuel pump relay.

What Does the 15-Amp Fuel Pump Fuse Protect?

The 15-amp fuel pump fuse in the 1991 Caprice does not just protect the fuel pump itself. It also protects several other components in the same circuit. This is important to know because if the fuse blows, any of these parts could be causing the problem.

The fuse protects the following:

  • Fuel Pump Relay: The relay that sends power to the fuel pump.
  • Fuel Pump: The electric pump inside the gas tank.
  • Engine Oil Pressure Switch: A backup safety switch that provides power to the fuel pump if the relay fails.
  • Powertrain Control Module (PCM): The engine computer, which also gets power from this circuit.

So if you have a blown fuel pump fuse, the problem could be a shorted fuel pump, a bad relay, a failing oil pressure switch, or even a wiring issue in the engine computer harness.

How to Check the Fuel Pump Fuse on a 1991 Caprice

Checking the fuse is easy and takes less than five minutes. Here is how to do it properly.

Step 1: Locate the fuse box under the hood. As described above, it is on the passenger side near the firewall.

Step 2: Open the fuse box lid. Some lids have clips on the sides that you squeeze to release. Others have a simple tab you pull up.

Step 3: Find the 15-amp fuel pump fuse. Look at the diagram on the underside of the lid or on the fuse box itself. It should be labeled "F/P" or "Fuel Pump." If no label exists, it is the 15-amp fuse in position number 2.

Step 4: Pull the fuse out. Use a fuse puller tool (usually stored inside the fuse box lid or inside the cabin fuse box) or a pair of needle-nose pliers. Grip the fuse gently and pull it straight out.

Step 5: Inspect the fuse. Hold it up to the light. Look through the clear plastic body at the metal strip inside. If the strip is intact and continuous, the fuse is good. If the strip is broken, melted, or looks separated, the fuse is blown.

Step 6: Test with a multimeter (optional but recommended). Set your multimeter to continuity test or resistance mode. Touch one probe to each of the two metal prongs on top of the fuse. If you hear a beep or see a reading near zero ohms, the fuse is good. If you see no continuity or infinite resistance, the fuse is blown.

What to Do If the Fuel Pump Fuse Is Blown

If you find that the 15-amp fuel pump fuse is blown, do not just replace it and assume the problem is fixed. A fuse blows for a reason, and replacing it without finding the cause will likely result in another blown fuse.

Step 1: Replace the fuse with a new 15-amp fuse. Do not use a higher amperage fuse (like 20 or 30 amps). Using a higher-rated fuse can cause wiring to overheat and start a fire.

Step 2: Try to start the car. If the engine starts and runs, the blown fuse was likely a one-time event caused by a momentary electrical spike. If the fuse blows again immediately or after a short drive, you have a real problem.

Step 3: Diagnose the underlying issue. If the fuse blows again, here are the most common causes to check.

Common Causes of a Blown Fuel Pump Fuse

1. A failing fuel pump. The most common reason for a blown fuel pump fuse is a fuel pump that is drawing too much current. As fuel pumps age, the internal motor can wear out, causing the pump to work harder and pull more amperage. This extra current eventually blows the fuse.

2. A shorted wire in the fuel pump circuit. The wiring that runs from the fuse box to the fuel pump relay, to the oil pressure switch, and all the way back to the fuel pump in the gas tank can rub against metal and develop a short circuit. This is especially common on older cars like the 1991 Caprice, where the plastic wire loom can become brittle and crumble, exposing bare wires.

3. A bad oil pressure switch. The oil pressure switch is wired into the fuel pump circuit as a safety backup. If this switch fails internally, it can cause a short that blows the fuse.

4. A failing PCM (engine computer). The fuel pump fuse also feeds power to the engine control module. If the PCM has an internal short, it will blow the fuse. This is less common, but it does happen.

Where Is the Fuel Pump Relay on a 1991 Chevy Caprice?

Many people confuse the fuel pump fuse with the fuel pump relay. They are two different components. The relay is the switch that turns the fuel pump on and off.

The fuel pump relay on a 1991 Chevy Caprice is located in the same engine compartment fuse box as the fuel pump fuse.

  • Location: Inside the under-hood fuse/relay box on the passenger side near the firewall.
  • Identification: The relay is usually labeled "Fuel Pump" on the fuse box cover. On the 1991 Caprice, the fuel pump relay is often identified as relay position "R5" in the fuse box.
  • Appearance: It looks like a small black or gray cube, about 1 inch square, with four or five metal prongs sticking out of the bottom.

If the fuel pump fuse is good but the pump still does not run, the next thing to check is the fuel pump relay. You can test it by swapping it with another relay of the same type in the fuse box (like the A/C compressor relay or the air pump relay) and seeing if the fuel pump starts working.

Symptoms of a Bad Fuel Pump or Blown Fuse in a 1991 Caprice

Knowing the symptoms can help you diagnose the problem before you even open the hood.

Engine cranks but does not start. This is the most common symptom. You turn the key, the starter motor spins the engine, but the engine never fires up.

No fuel pump whine. When you turn the key to the ON position (without cranking the engine), you should hear a faint humming or whining sound coming from the rear of the car for about two seconds. This is the fuel pump pressurizing the system. If you hear nothing, the fuel pump is not getting power.

Engine starts, then dies after a few seconds. This is a classic sign of a failing fuel pump or a bad oil pressure switch. The car starts because the fuel pump relay initially provides power, but then the engine stalls when the relay turns off and the oil pressure switch fails to take over.

Car runs rough or has no power. If the fuel pump is failing but not completely dead, it may not deliver enough fuel pressure. This can cause the engine to sputter, hesitate, or lack power, especially under load or going uphill.

Fuse blows repeatedly. If you replace the fuel pump fuse and it blows again immediately or after a short drive, you have a short circuit or a failing component drawing too much current.

How to Test the Fuel Pump Circuit on a 1991 Chevy Caprice

If you have a blown fuse or a no-start condition, here is a simple way to test the fuel pump circuit.

1. Check voltage at the fuse. With the key in the RUN position, use a multimeter to check for 12 volts at both sides of the fuel pump fuse location. If you have power on one side only, the fuse is blown.

2. Listen for the relay click. With the key in the RUN position, listen for a click from the under-hood fuse box. You should hear the fuel pump relay click on for about two seconds, then click off. If you hear no click, the relay may be bad, or the PCM is not sending the signal to turn the relay on.

3. Test the fuel pump relay. Remove the relay from the fuse box. Use a multimeter to check for continuity between the relay's coil terminals. Apply 12 volts to the coil terminals and listen for the relay to click. If it does not click, the relay is bad.

4. Check fuel pressure. The 1991 Caprice with a 5.0L engine should have 9 to 13 PSI of fuel pressure at the throttle body when the pump is running. Connect a fuel pressure gauge to the test port on the throttle body (TBI unit) and turn the key to ON. If you see no pressure, the pump is not running, or the fuel line is clogged.

What to Do If the Fuel Pump Fuse Is Good but the Pump Still Does Not Run

If you have checked the fuel pump fuse and it is good, but the pump still does not run, the problem is elsewhere.

Possible causes include:

  • A bad fuel pump relay. The relay may have failed internally.
  • A dead fuel pump. The pump itself may have worn out. On a 1991 Caprice, fuel pumps often fail after 100,000 miles.
  • A bad oil pressure switch. The oil pressure switch is wired in parallel with the fuel pump relay. If both the relay and the switch fail, the pump will not run.
  • A wiring problem. A broken wire, a corroded connector, or a loose ground can prevent power from reaching the pump.
  • A bad PCM. The engine computer controls the fuel pump relay. If the PCM fails, it may not ground the relay coil to turn the pump on.

Why You Should Replace Your 1991 Chevy Caprice Fuel Pump with KEMSO

If you have diagnosed the problem and found that your fuel pump is bad, you need a reliable replacement. The fuel pump on a 1991 Caprice is a critical component, and using a cheap, low-quality pump can leave you stranded on the side of the road.

This is where KEMSO Fuel Pumps come in. KEMSO specializes in high-performance, direct OEM replacement fuel pumps that are built to last. Every KEMSO fuel pump is designed to meet or exceed the original factory specifications for your vehicle.

Here is why KEMSO is the right choice for your 1991 Chevy Caprice:

1. High Performance. KEMSO fuel pumps are engineered for high flow rates and consistent fuel pressure. They support up to 200 liters per hour, compared to the original pump's flow of only 60 to 80 liters per hour. This means your engine will get all the fuel it needs, even under heavy load.

2. Direct OEM Replacement. KEMSO pumps are designed to bolt right in, with no modifications needed. They fit perfectly in your 1991 Caprice's fuel tank, just like the original factory pump.

3. Lifetime Warranty. Every KEMSO fuel pump comes with a lifetime warranty. This is not just a marketing gimmick. KEMSO stands behind their products. If your fuel pump ever fails, it will be replaced at no cost to you. This is the kind of confidence that comes from building high-quality products.

4. Built for Durability. KEMSO pumps are designed for use with gasoline and ethanol blends. They feature a bypass valve set at 125.8 PSI, which is higher than the original performance standard, ensuring reliable operation under all conditions.

5. USA-Based Support. KEMSO provides customer support from the United States, with technicians who understand American vehicles like the 1991 Chevy Caprice.

If you are replacing the fuel pump on your 1991 Chevrolet Caprice, do not settle for a cheap imitation. Invest in a KEMSO fuel pump and enjoy the peace of mind that comes with a lifetime warranty.

Visit KEMSO today at https://www.kemsoracing.com/ to find the perfect fuel pump for your Chevy Caprice. Their website has a full catalog of fuel pumps for cars, trucks, motorcycles, ATVs, and more. With a lifetime warranty and a reputation for quality, KEMSO is the smart choice for anyone who wants their engine to run reliably for years to come.

Final Thoughts on the 1991 Chevy Caprice Fuel Pump Fuse

To summarize the key points:

The fuel pump fuse on a 1991 Chevy Caprice is a 15-amp fuse located in the engine compartment fuse box on the passenger side near the firewall. It is in position number 2 and is labeled "F/P" or "Fuel Pump."

The fuse protects the fuel pump relay, the fuel pump, the oil pressure switch, and the PCM. If the fuse blows, the engine will not start, and you will not hear the fuel pump run.

Always check the fuse first when diagnosing a no-start condition on your 1991 Caprice. If the fuse is blown, replace it with a 15-amp fuse and test the car. If the fuse blows again, you have an underlying issue that needs to be fixed before driving the car.

Common causes of a blown fuel pump fuse include a failing fuel pump, a shorted wire, a bad oil pressure switch, or a failing PCM.

If you need to replace the fuel pump, choose a high-quality, reliable replacement. KEMSO fuel pumps offer high performance, direct OEM fitment, and a lifetime warranty. Visit https://www.kemsoracing.com/ to find the right fuel pump for your 1991 Chevy Caprice and get back on the road with confidence.


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