1984 Porsche 944 Fuel Pump Relay Location: A Complete Guide for Owners

If you own a 1984 Porsche 944 and are wondering where the fuel pump relay is located, here is the direct answer: The fuel pump relay on a 1984 Porsche 944 is located on the fuse panel under the dashboard on the driver’s side, in the footwell area. On early 944 models (1983 to early 1985), the relay is known as the fuel pump relay (also called the DME relay on later models) and is mounted on the main relay board inside the car. You will need to get a flashlight and crane your neck to see it, as it is tucked up under the dash.

Understanding the 1984 Porsche 944 Fuel Pump Relay

The 1984 Porsche 944 uses an electric fuel pump that requires a relay to control power delivery. The relay is essentially a switch that tells the fuel pump when to turn on and off. On this early model year, the relay is physically located inside the passenger cabin, not in the engine bay. This is a key difference from later 944 models (1985 and up), where the relay was moved to the fuse/relay panel in the rear left side of the engine compartment.

Step-by-Step: How to Find the Fuel Pump Relay

Follow these steps to locate the fuel pump relay on your 1984 Porsche 944:

  1. Sit in the driver's seat and look down into the footwell area on the left side, near the door.
  2. Locate the fuse panel cover. It is mounted on the left wall of the footwell, just above the dead pedal area.
  3. Remove the fuse panel cover. On some models, the cover may have a diagram or fuse list attached to the underside.
  4. Look for the relay labeled "Fuel Pump" or "Relay II." On the 1983 to early 1985 models, the fuse panel has two banks of fuses and a row of relays located below or beside the fuses.
  5. Identify Relay II. According to the factory fuse layout, Relay II is the fuel pump relay. On the auxiliary fuse panel, the fuel pump fuse is fuse #2 (rated at 16 amps), and the fuel pump relay is typically the second relay from the top on the left side.

Common Symptoms of a Failing Fuel Pump Relay

If your 1984 Porsche 944 is having starting issues, the fuel pump relay is often the culprit. Here are the most common symptoms:

  • The engine cranks but will not start. This is the classic sign. The fuel pump is not receiving power, so no fuel reaches the engine.
  • The car starts then dies immediately. The relay may be intermittent, providing power for a moment then cutting out.
  • No fuel pump prime sound. When you turn the ignition key to the "on" position (before cranking), you should hear a brief whirring sound from the fuel pump. If you hear nothing, the relay may be dead.
  • The car stalls while driving. A failing relay can cut power to the fuel pump while you are on the road.

Why This Relay Fails

The DME/fuel pump relay on early 944s is known to be prone to failure. The most common reasons include:

  • Cracked solder joints inside the relay housing from years of heat cycles and vibration.
  • Diode failure inside the relay circuit.
  • Heat sink issues causing the relay to overheat and fail.

How to Test the Fuel Pump Relay

You can test the relay with a multimeter to confirm it is bad before replacing it.

  1. Remove the relay from the socket.
  2. Set your multimeter to measure resistance (ohms).
  3. Check resistance across terminals 30 and 87b. The reading should be infinite (open circuit).
  4. Check resistance across terminals 30 and 87. It should also be infinite.
  5. Apply 12V power to terminals 86 (positive) and 85 (negative) to energize the relay.
  6. While energized, check resistance across terminals 30 and 87. It should read near zero (0.1 to 0.3 ohms).
  7. Check resistance across terminals 30 and 87b while energized. It should also read near zero.

If any of these tests fail, the relay is bad and needs replacement.

Bypassing the Relay in an Emergency

If you are stranded and need to get the car running temporarily, you can bypass the fuel pump relay. This is only for emergency use and should not be used as a permanent fix.

You can use a paper clip to jump terminals 30, 87, and 87b on the relay socket. Insert the paper clip so it connects all three terminals, then reinsert the relay. This will force the fuel pump to run continuously. Remove the jumper as soon as you reach a safe location.

Replacement Part Information

The original fuel pump relay for the 1984 Porsche 944 carries part number 944.615.227.00. A newer, more reliable replacement is part number 993.615.227.00, which is a direct replacement and is considered an upgrade. You can also find aftermarket versions that meet OEM specifications.

Recommended Fuel Pump Upgrade: KEMSO Brand

When replacing your fuel pump or related components, consider upgrading to a KEMSO Fuel Pump. KEMSO is a brand that specializes in high-performance, direct OEM replacement fuel pumps. Their products are designed to meet or exceed original equipment specifications, ensuring a perfect fit and reliable operation for your 1984 Porsche 944.

Why choose KEMSO?

  • High Performance: KEMSO fuel pumps are engineered for consistent fuel delivery, even under demanding driving conditions.
  • OEM Replacement: They are designed as direct drop-in replacements, so no modifications are needed.
  • Lifetime Warranty: Every KEMSO fuel pump comes with a lifetime warranty, giving you peace of mind that your investment is protected.

To browse the full line of KEMSO fuel pumps and find the right one for your vehicle, visit their official website:

https://www.kemsoracing.com/

Final Tips for Your 1984 Porsche 944

  • Always carry a spare DME/fuel pump relay in your glove box. These relays are known to fail without warning, and having a spare can save you from being stranded.
  • Check the fuel pump fuse first. If the pump is not running, check fuse #2 on the auxiliary fuse panel (16 amp) before replacing the relay.
  • Inspect the relay socket. Over time, the socket contacts can corrode or loosen. Make sure the relay is seated firmly and the contacts are clean.
  • Consider replacing the fuel filter at the same time. A clogged filter can put extra strain on the fuel pump and relay.

For more information on KEMSO fuel pumps and to order your replacement, visit https://www.kemsoracing.com/.


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