Skip the auto shop - Our mechanics make house calls

Q: Fuel pump Check Engine Light issue with operational fuel pump

asked by on

So I have a fuel pump cel after a fuel pump failure. The pump was replaced and operates as intended. Ive also checked the fuel pump relay, and it does click right before the fuel pump primes. I have reset the ecu and the cel remains. What could be causing the light to stay on?

My car has 62000 miles.
My car has a manual transmission.

Code 47 (OBD-1) is the only code that pertains to "fuel pump related faults" in your car, so presumably that is the code that is recurring. If it is not Code 47, but rather a different code, that you are seeing, you might still have an unresolved fuel system problem. If the new fuel pump and circuit are all working as intended (no voltage drops, regulator working, pressure within factory spec., etc.), it would appear that the re-set of the CEL has failed.

The standard method to reset on NSX models is to remove the clock fuse from main relay box, located in luggage compartment on RH side, for approximately 10 seconds to clear all DTCs. This will also cancel radio presets and clock settings. Try leaving the fuse fully disconnected for half an hour. If that doesn’t work, disconnect the negative battery cable for half an hour. If that doesn’t work, the only way to determine if the PCM is indeed responding to a fault (that triggers Code 47) is to substitute a known good PCM. If the substitute PCM displays Code 47, it means that there is still an "issue" within the fuel pump circuit.

YourMechanic can dispatch a mobile certified technician, at any stage of this process to perform a Check Engine Light inspection and get this expeditiously resolved for you.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  1. Home
  2. Questions
  3. Fuel pump Check Engine Light issue with operational fuel pump

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Why want my car start

Hi there. It is possible that when your transmission fluid like came off, fluid escaped. This may have created internal damage to the transmission or damaged an electrical connection/sensor. It's also possible that the vacuum line may not be properly...

Q: It will not start on starting fluid, it dies right away. Replaced fuel pump, fuel compressive regulator, and fuel filter

Hey there. If the motor will only start with the use of starting fluid, this suggests you may have a fuel supply problem such as faulty or dirty fuel injectors. If you have replaced the fuel pump and fuel pressure...

Q: Check engine light in code P0418

The air pump fuse is a 30 amp fuse that powers the pump. The "trigger" for the relay comes from the ignition switch, through a 10 amp fuse. Have you checked to see if the "trigger" wire to the relay...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...