2005 G35 Fuel Pump Location: Where to Find It and How to Replace It Yourself
The bottom line up front: The main fuel pump on a 2005 Infiniti G35 is located inside the fuel tank under the rear passenger-side seat cushion. You do not need to drop the fuel tank to access it. Simply remove the rear seat bottom, take off the metal access cover, and you will see the pump assembly right there. The secondary fuel level sender is located on the driver’s side under the same rear seat.
If your G35 is cranking but not starting, stalling unexpectedly, or making a loud whining noise from the back seat area, the fuel pump is a likely suspect. This guide walks you through exactly where the pump is, how to get to it, and what to do when it fails.
Why Knowing the 2005 G35 Fuel Pump Location Matters
The 2005 Infiniti G35 uses a saddle-shaped fuel tank, which means it has two separate compartments. Because of this design, the car needs two sensors to accurately measure fuel level. The main fuel pump assembly sits on the passenger side and contains the electric pump, the fuel pressure regulator, and a fuel level sending unit. The driver’s side holds only a secondary fuel level sending unit.
Knowing this saves you time and money. If your fuel gauge is acting up but the car runs fine, the problem may be the driver’s side sender, not the pump itself. If the car stalls or fails to start, the issue is almost certainly the pump on the passenger side. Understanding the 2005 G35 fuel pump location helps you diagnose the problem without guesswork.
Symptoms of a Failing Fuel Pump in a 2005 Infiniti G35
Before you start digging into the rear seat, it helps to confirm the fuel pump is actually the problem. Here are the most common symptoms owners report:
- Engine cranks but will not start. You turn the key, the starter spins the engine, but it never fires up. This is the classic sign of no fuel pressure.
- Stalling while driving. The engine dies suddenly, especially during hot weather or after long drives. It may restart after sitting for a while.
- Loud whining noise from the rear seat area. A healthy fuel pump makes a subtle hum when you turn the key to the ON position. A failing pump often gets loud and noisy before it quits entirely.
- Sputtering at high speeds. The car feels like it is running out of gas even when the tank is full. This happens because the pump cannot maintain pressure under load.
- Loss of power during acceleration. The engine hesitates or bogs down when you step on the gas.
- Check engine light comes on. Common codes include P0087 (fuel rail pressure too low) or P0183 (fuel temperature sensor circuit).
If you notice one or more of these symptoms, start by checking the fuel pump location on your 2005 G35 before paying a shop for a diagnosis.
Step-by-Step: How to Access the 2005 G35 Fuel Pump
Replacing the fuel pump on a 2005 Infiniti G35 is a DIY-friendly job. The difficulty level is about 2.5 out of 5. You do not need to drop the fuel tank or remove the exhaust system. Here is exactly how to do it.
Tools and Parts You Will Need
- New fuel pump assembly (OEM replacement or high-quality aftermarket like KEMSO)
- New O-ring seal (part number 17342-CE800 is the factory seal)
- 8mm socket and ratchet
- Phillips screwdriver
- Needle-nose pliers
- Rag and a small container for any spilled fuel
- Safety glasses and gloves
- Fuel line disconnect tool (optional but helpful)
Step 1: Relieve Fuel System Pressure
This is a critical safety step. Gasoline is extremely flammable. Locate the fuel pump fuse in the fuse box (under the dash or in the engine bay). Start the engine, then pull the fuse. The engine will stall after a few seconds. Crank the engine for another 2-3 seconds to clear any remaining pressure from the lines.
Step 2: Disconnect the Battery
Remove the negative battery terminal. This prevents any sparks near the fuel system while you work.
Step 3: Remove the Rear Seat Cushion
The rear seat bottom is held in by two clips at the front edge. Firmly pull up on the front of the seat cushion. It will pop loose. Then pull the cushion forward and out of the car. This gives you full access to the floor pan.
Step 4: Locate the Access Panel
On the passenger side, you will see a round black metal cover plate held down by four Phillips screws. Remove these screws and lift the cover off. This is your direct access to the 2005 G35 fuel pump location.
Step 5: Disconnect the Electrical Harness and Fuel Line
Clean any dirt and debris from around the access opening before proceeding. Disconnect the electrical connector by pressing the tab and pulling it apart. Then disconnect the quick-disconnect fuel line. Push the release button or use a fuel line tool to separate it. Have a rag ready; a small amount of fuel may spill.
Step 6: Remove the Pump Assembly
Use an 8mm socket to remove the 6 or 8 bolts holding the pump assembly to the tank. Lift the pump straight out of the tank. Be careful not to bend the float arm or snag it on wires inside the tank. The assembly will be heavy because it still contains fuel. Set it aside in a fuel-resistant container.
Step 7: Install the New Pump
Transfer the new O-ring seal to the tank opening. Lower the new pump assembly into the tank, making sure the float arm is oriented correctly. Tighten the bolts in a criss-cross pattern. Reconnect the fuel line and electrical harness. Install the access cover, then reinstall the rear seat cushion.
Step 8: Test the System
Reconnect the battery and reinstall the fuel pump fuse. Turn the ignition to the ON position for 2 seconds, then turn it off. Repeat this 3 times to prime the system. Check for leaks. Start the engine and let it idle for a minute. Check for leaks again. Take the car for a test drive to confirm the repair.
Common Mistakes to Avoid When Replacing the 2005 G35 Fuel Pump
Using a Cheap Aftermarket Pump
Many G35 owners try to save money by buying a cheap new aftermarket pump. These pumps are notorious for premature failure. They can fail within months, forcing you to do the entire job again. They may also have incorrect resistance values in the sending unit, causing the fuel gauge to read wrong.
Not Replacing the O-Ring
The rubber O-ring that seals the pump assembly to the tank is a wear item. If you reuse the old one, it may leak fuel and fumes into the cabin. The factory O-ring part number is 17342-CE800. Always install a new one.
Forcing the Pump Assembly
The plastic pump housing is fragile. If you force it into the tank, you can break the float arm or the internal components. Lower it gently and rotate it slightly if it does not drop in smoothly.
Ignoring the Driver’s Side Sender
If your fuel gauge is still wrong after replacing the pump, the problem may be the secondary sending unit on the driver’s side. That unit is also accessible under the rear seat and is easy to replace.
Cost of Replacing the 2005 G35 Fuel Pump
The total cost depends on where you buy the parts and whether you do the work yourself. Here is a realistic breakdown:
| Item | Estimated Cost |
|---|---|
| New OEM fuel pump (dealer) | $650 - $1,400+ |
| New OEM fuel pump (online) | $420 - $560 |
| New aftermarket fuel pump (budget brands) | $65 - $325 |
| Used OEM fuel pump | $50 - $150 |
| High-quality aftermarket (KEMSO) | $79.98 |
| O-ring seal | $5 - $15 |
| Shop labor | $110 - $200 |
| Dealer total (parts + labor) | $1,425 - $1,479 |
As you can see, doing the job yourself with a quality pump saves a significant amount of money. The dealer wants over $1,400, but you can complete the repair for under $100 in parts.
Why a Used OEM Pump or a High-Quality Aftermarket Pump Is the Smart Choice
When replacing the fuel pump on your 2005 G35, you have several options. Here is what you need to know about each.
New OEM (Dealer)
This is the most expensive option. A new genuine Infiniti pump from the dealer costs $650 to over $1,400. The part is guaranteed to fit, but you are paying a steep premium for the Infiniti name.
Cheap Aftermarket (Budget Brands)
These pumps cost $65 to $325. They are often poorly made and fail prematurely. Many owners report that cheap pumps die within 6 to 12 months. The fuel gauge may also read incorrectly because the sending unit has the wrong resistance values. Avoid these unless you enjoy doing the job twice.
Used OEM from a Recycler
A used OEM pump from a low-mileage donor car costs $50 to $150. This is a good budget option if you verify the mileage and condition. The pump has already proven its quality, and it will fit correctly. However, it is still a used part with unknown history.
High-Quality Aftermarket (KEMSO)
This is the best balance of cost, performance, and reliability. KEMSO fuel pumps are designed as direct OEM replacements and offer superior flow rates. They deliver up to 200 liters per hour at 43 psi, which is significantly more than the stock pump. Every pump comes with a lifetime warranty. If it ever fails due to a manufacturing defect, KEMSO replaces it for free. This is a massive advantage over dealer parts, which only carry a 1- or 2-year warranty.
Why You Should Buy a KEMSO Fuel Pump for Your 2005 Infiniti G35
When it is time to replace the fuel pump on your 2005 G35, KEMSO offers the best value on the market. Here is why American drivers choose KEMSO over the competition:
- OEM Replacement Fit. KEMSO pumps drop directly into the factory location. You do not need adapter kits, modifications, or special tools. Everything fits exactly like the original part.
- High Performance. The stock G35 fuel pump delivers roughly 60-80 liters per hour. KEMSO pumps deliver up to 200 liters per hour at 43 psi. This extra capacity ensures your engine never runs lean, even under heavy load or if you have performance modifications.
- Lifetime Warranty. Every KEMSO fuel pump has a serialized body and is backed by a lifetime warranty. If the pump ever fails due to a manufacturing defect, KEMSO replaces it at no cost. No other aftermarket brand offers this level of protection.
- Ethanol and E85 Compatible. Many gas stations now use E15 or E85 blends. Standard rubber seals swell and crack when exposed to ethanol. KEMSO uses Viton-lined components that resist ethanol degradation. This makes them a smart long-term investment for any American driver.
- Complete Kit. When you buy a KEMSO fuel pump, you get everything needed for installation: the pump, gradient density fuel strainers, flex hoses, Viton O-rings, wiring connectors, and clamps. There is no need to buy extra parts.
You can see the full selection of KEMSO fuel pumps for the Infiniti G35 and hundreds of other vehicles at: https://www.kemsoracing.com/
Frequently Asked Questions About the 2005 G35 Fuel Pump Location and Replacement
Do I have to drop the fuel tank to replace the pump?
No. The 2005 G35 fuel pump location is under the rear passenger-side seat cushion. You access it through a service port in the floor pan. You never need to drop the tank.
Can I just replace the pump motor instead of the whole assembly?
Yes, you can replace just the electric pump motor inside the plastic housing. This is a cheaper option but requires disassembling the unit. For most DIYers, replacing the entire assembly is faster, simpler, and ensures the fuel pressure regulator and sending unit are fresh.
Why is my fuel gauge still wrong after replacing the pump?
This is a common problem. It can be caused by three things:
- The float arm was bent or snagged during installation.
- The secondary sending unit on the driver’s side is also faulty and needs replacement.
- You used a cheap aftermarket pump with an out-of-spec sending unit.
If you used a quality pump like KEMSO and the gauge is still wrong, check the driver’s side secondary sender.
What is the part under the driver’s side rear seat?
That is the secondary fuel level sending unit. Because the G35 has a saddle-shaped fuel tank, it needs two sensors to get an accurate fuel reading. The driver’s side unit is only a sensor. The pump is on the passenger side.
Will a fuel pump from a Nissan 350Z fit my 2005 G35?
Sometimes, but you must be careful. The G35 and 350Z share the VQ35DE engine and similar fuel systems. A pump from a 2006 350Z will often work in a 2006 G35 Coupe. However, you must verify the part number and visually confirm that the electrical connector and hose ports are identical before purchasing.
What fuel pressure should the 2005 G35 fuel pump deliver?
The stock system operates at approximately 51 PSI. The fuel pump is typically rated to deliver 50-55 PSI under normal conditions. If you are building a high-performance setup, you may need an upgraded pump to reliably maintain 58 PSI.
Summary: 2005 G35 Fuel Pump Location and What to Do When It Fails
The main fuel pump on a 2005 Infiniti G35 is located under the rear passenger-side seat cushion inside the fuel tank. The secondary fuel level sender is on the driver’s side. You can access both without dropping the tank.
If your G35 is cranking but not starting, stalling, or making a loud whining noise from the back seat, the fuel pump is likely the cause. Replacing it yourself takes about 2-3 hours and saves you over $1,000 compared to dealer repair costs.
When choosing a replacement, avoid cheap aftermarket pumps that fail quickly. A high-quality aftermarket pump like KEMSO delivers superior performance, includes a lifetime warranty, and fits perfectly in the factory 2005 G35 fuel pump location. You can order yours today at: https://www.kemsoracing.com/