Is it true that if a fuel pump fails, it will not show up on a diagnostic report until it completely fails?

Is it true that if a fuel pump fails, it will not show up on a diagnostic report until it completely fails?

My car has 120000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
Hi There,
Unfortunately, there is no sure indicator to know whether or not the fuel pump failure would show up prior to it failing completely, however when it begins to fail, usually there will be a fuel pressure fluctuation, which should set off other indicators related to a lean fuel condition or problems with fuel injectors not putting out the correct amount of fuel due to the change in fuel pressure.

How to Identify and Fix Common car Problems ?

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Can a fuel pump go out without warning? Absolutely! A car fuel pump will fail without warning more often than you may think. All things related to a car fuel pumps like the injectors, the pressure regulator, and the car fuel pump itself are the part that are most replaced with the fuel system.
Sputtering Engine

Your fuel pump doesn`t stop pushing gas through to the engine once you`ve started your vehicle; it also pumps gas to meet your vehicle`s speed. If the pump cannot produce a constant stream of gas at higher speeds, your vehicle`s engine will sputter and threaten to stall.

A weak fuel pump may throw off your car`s air/fuel ratio, causing the engine control module (ECM) to turn on the check engine light. In some cases, pump electrical issues may trigger the light as well.
To confirm that your pump has failed, check the pressure in your fuel lines with a fuel pressure gauge; if it reads zero, then your pump is likely dead. You can also check your car`s fuse box; a blown fuel pump fuse is another reliable symptom of a failed pump.
Because fuel pumps constantly run whenever the ignition is turned on, they can eventually wear out and weaken over time. A weak fuel pump may still pump fuel, but the vehicle may experience difficulty starting from the lack of pressure.
With the fuel pressure gauge attached, start the engine and let it idle. Disconnect the vacuum hose from the pressure regulator; the pressure should drop approximately 8 to 10 PSI. If it does not, suspect a problem with the regulator or its` vacuum supply.
Fuel pump failures can be caused by electrical faults, old age (wear) or fuel contaminants (dirt, moisture or bad gas). Fuel pump failures often occur without warning. Fuel pumps, injectors and pressure regulators are the three most commonly replaced fuel system components.
The P0230 code indicates an issue with the fuel pump. This generic code indicates that there`s an issue with the circuit between the fuel pump and the powertrain control module (PCM).
About the Lexus and Toyota Fuel Pump Recall

A total of 1.5 million cars from the U.S. have recalled for potential engine stalls and fuel pump failures. The recall covers both Toyota and Lexus models, from 2013 to 2020. At least 40 models are affected.

After 100,000 miles, the failure of the pump is likely enough that if you are replacing a major part in the fuel system nearby, it may be advantageous to replace it at the same time.
The average fuel pump lasts for more than 100,000 miles and sometimes longer, so more than likely, you won`t have to worry about it failing for quite a while. But the more miles your car accumulates, the more liable you are to run into a failed fuel pump.
After placing the rag under the test port, install the pressure tester to the port. Then start the engine and start recording the pressure reading. You can check the manufacturer`s manual on pressure testing the fuel pump. Some manufacturers suggest checking the pressure with the engine running at a particular RPM.
Fuel Pump. Finally, your fuel pump can get clogged by gas sediment, dirt, and rust. The fuel pump is susceptible to clogs because it draws the gas out of the tank.
A bad fuel pump may overheat and inadequately deliver gas to the engine, causing it to run hot and turn off while on the road. In this scenario, your vehicle may start back up after overheating and shutting down, only to do the same thing a half-hour later.
Fuel pump failures tend to be sudden and unpredictable, with few symptoms to warn the motorist that trouble is brewing. And the higher the mileage on the vehicle, the greater the risk of a fuel pump failure.
Fuel pump failures often occur without warning. Fuel pumps, injectors and pressure regulators are the three most commonly replaced fuel system components. Problems with any of these may prevent an engine from starting or cause serious drivability or performance problems.
After 100,000 miles, the failure of the pump is likely enough that if you are replacing a major part in the fuel system nearby, it may be advantageous to replace it at the same time.
Fuel pump failures often occur without warning. Fuel pumps, injectors and pressure regulators are the three most commonly replaced fuel system components. Problems with any of these may prevent an engine from starting or cause serious drivability or performance problems.
After 100,000 miles, the failure of the pump is likely enough that if you are replacing a major part in the fuel system nearby, it may be advantageous to replace it at the same time.
The most common reason a pump fails is wear on the pump from improper lubrication or over-use. The best way to explain a failed fuel pump due to wear and tear is to explain what other reasons may have lead to a failed pump: Most fuel pumps are lubricated by the fuel in the tank itself.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Is it true that if a fuel pump fails, it will not show up on a diagnostic report until it completely fails?
ANSWER : Hi There,
Unfortunately, there is no sure indicator to know whether or not the fuel pump failure would show up prior to it failing completely, however when it begins to fail, usually there will be a fuel pressure fluctuation, which should set off other indicators related to a lean fuel condition or problems with fuel injectors not putting out the correct amount of fuel due to the change in fuel pressure.

Just replaced my fuel pump but its not getting any power tested fuel pump relay and fuel fuse both good tested the wires all good.
ANSWER : You need to look at the theft light on dash to make sure it comes on and goes off when you turn the key to the on position. If light comes on and stays on then your theft system is causing the fuel pump to not be engaged. I recommend you check the theft system and then scan the computer for theft system codes. You may need to reprogram the keys to work or you have an bad sensor for the ignition key in the steering column.

Engine crank, no coil spark, fuel pump does not kick in.
ANSWER : Hi there. There could be multiple issues causing your lack of spark problem, ranging from a minor electrical short in the main relay to an issue with your ECU. In order to know for sure, you should have a professional mobile mechanic complete an electrical problems inspection.

Replaced fuel pump. Car won’t start. 2002 Infinity I35
ANSWER : Hi there – the metal component you describe is a fuel check valve on the fuel return line. Its function is to maintain a small amount of pressure in the fuel system so that starting does not require the fuel pump to run very long before the engine will start. Having replaced the fuel pump and fuel filter, I would check fuel pressure while the car is running. This is to check the fuel pump relay for burned contacts that won’t support full electrical current to the pump, and for proper fuel pressure – a malfunctioning fuel pressure regulator could also restrict power and higher speeds if pressure is too low. I would recommend an inspection of the fuel system by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

I have a 1981 e-350 with dual fuel tanks the p.o. added a third tank and 3 electric fuel pumps along with sepparate gauges and swi
ANSWER : The switch you are referring to is vended with the required electrical and fuel schematic (I just looked in the box) that answers your installation question. If you want an advance view, here is a link as well. Yes, you need a return line and just refer to the aforementioned link. If you are retrofitting back to OEM, I strongly encourage you to buy the original Factory Service Manual (FSM). There are lots of details attending this system and obviously it is difficult to recount it all here. The FSM will make your life much easier and you can then make sure your installation is perfect. Alternatively, YourMechanic can dispatch a certified mechanic and perform the whole retrofit and check out if you desire. Just request and schedule a generic service such as fuel pump service and the mechanic will come to your location and estimate the parts and labor required. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Installed new delphi fuel pump and fram fuel filter. still no pressure on fuel rail valve and wont start. 2003 Chevrolet Tahoe
ANSWER : Hi there – I suspect you have weak power getting to the fuel pump. I would first check the voltage coming out of the fuel pump relay. If the contacts in the relay are burned, you will not get reliable current flow to the pump. Check the fuel pump ground as well (voltage drop across the ground, not just continuity). I recommend a fuel system inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

Fuel pressure
ANSWER : Hello,
You may want to try checking the fuel pump relay. The relay wires should have ground on two wires, power on one wire and switched power on another wire. To activate the fuel pump your ECU actually connects one of the ground wires to complete the circuit and send power to the fuel pump. If the wires all have power running through them, then it is likely you have a faulty relay. The wire coming from the fuel pump is the other ground wire. I would recommend having an expert from YourMechanic come to your location to diagnose your wiring as this can be very difficult and time consuming without the proper wiring diagram.

Car only runs when jumper the fuel pump
ANSWER : Check to see if you are getting power when you test the green with orange stripe wire going to the fuel pump module. If you have no power then check the the fuel inertia switch, in the left kick panel, by the drivers foot, and see if the inertia switch is not tripped. If it is, reset it and the pump should work.

If the switch is okay then make sure it has power to it and from it, when cranking the engine. If you have no power then check the fuel relay and see if it has power to it and that it’s being turned on when you crank it. If you do not then you may have an issue with the computer not activating the fuel pump. This will require a scan of the system and in-depth tests further than the scope of what this diagnoses is capable of. You will need a wiring diagram to follow and a scanner to activate the relays to test the system.

If you decide to get this fixed, contact a certified mechanic who can perform all of these checks in order to find the root of your starting problem. Once this is done, an accurate repair can be made.