Can A Bad Fuel Pump Relay Cause Misfire? (Yes, It Can)

Ever wondered where the fuel pump of your car receives enough power to operate properly? Well, your car is equipped with a fuel pump relay, a kind of electrical device that sends currents to the fuel pump to function correctly.

Yes, a bad fuel pump relay can cause misfire, it can also cause other problems too. I have explained it all. Also read about the symptoms of bad fuel pump so you can detect early.

Can a bad fuel pump relay cause misfire
Can a bad fuel pump relay cause misfire?

If your car’s fuel pump is faulty or damaged, it is quite easy to troubleshoot; you just need to look for certain symptoms of it, which include- Stalling of the car, no noise coming from the fuel tank, etc. A faulty fuel pump relay can cause engine issues as well as misfires. Also, don’t worry if your car does misfire.


Can a bad fuel pump relay cause misfire?

A bad fuel pump relay can cause various problems in your car, but the most common problem that it causes is engine misfiring. Yes, a bad fuel pump relay can result in the misfiring of your engine not.

Only that, it can lead to ignition issues as well. The reason for this is quite evident as the fuel pump relay is a part of the fuel system, and defects in the fuel system will hamper the engine’s functioning simultaneously.

But it is not that every time an engine misfire occurs, it is because of the defect in the fuel pump relay. It can also be due to the faulty spark plugs in your car. But make sure to troubleshoot the cause of this issue of engine misfiring; in this article, we will discuss further ways to deal with this issue and know more about it.


What are the symptoms of a bad fuel pump relay?

In this section of this article, we will discuss all the symptoms of a damaged fuel pump relay; look for these symptoms if you doubt something is wrong with the fuel pump relay of your car.

What are the symptoms of a bad fuel pump relay?
What are the symptoms of a bad fuel pump relay?

πŸš— The problem in starting your car

If you are having problems starting your car, then it is a clear indication that something is wrong with the fuel system of your car, specifically the fuel pump relay, which is quite common to cause this issue in your car. But most of the time, people consider it an act of a dead battery or rusty wiring. That might be the reason every time, but it is not.

πŸš— Illuminate engine light

Notice for illuminated engine light on your dashboard, which signifies that something is wrong with your engine or its sub-connected parts.

Suppose this light pops up on your dashboard. In that case, it might be possible that the fuel pump relay may be damaged as it is also a main component of the fuel system and is connected to the fuel pump, which directly connects to the engine for delivering fuel that will then be used in the process of combustion.

Stalling the engine can be another big sign that your fuel system or its significant parts are damaged or not functioning properly. The most common part that might be responsible for stalling is the fuel pump relay.

A damaged fuel pump relay will not deliver the appropriate amount of power to the fuel pump so that it can transfer the fuel to the engine correctly, which results in improper combustion in the engine and leads to stalling.

πŸš— No noise from the fuel pump

Β If your car has a damaged fuel pump relay, then it can easily be diagnosed by simply checking the noise that comes from the fuel pump; if there is a rushing noise coming from the fuel pump of your car then it means that your fuel pump relay is fine, but if not then there is an issue with the fuel pump relay of your car.


What happens when a fuel relay goes bad?

This section of this article will discuss all the problems that come with a bad fuel pump relay. If you have a bad fuel pump relay, you might or might not be witnessing these issues in your car:

What happens when a fuel relay goes bad?
What happens when a fuel relay goes bad?

πŸš— Loss of power in your car

If you have a bad fuel pump relay, you might not be able to accelerate your car at the usual time. This is because an incorrect air-fuel mixture or an irregular amount of powered fuel reaching the engine can reduce the vehicle’s power.

πŸš— Lower fuel economy

If your car has a bad fuel pump relay, then there is a high chance that your car will suffer a lower or disturbed fuel economy which is quite common to experience as it mostly occurs when there is any default with the engine or the sub-connected parts to it.

πŸš— Jerking of the car

A bad or faulty fuel pump relay can also be the reason for the frequent jerking of the car; this is bound to happen if something goes wrong with your car’s fuel system.


What Can Damage A Fuel Pump Relay?

The most common cause for your fuel pump relay to get damaged is the sudden increased power that causes the voltage to increase rapidly and results in burning the contacts of the fuel pump relay of your car, eventually damaging the fuel pump relay.

It can also be possible due to a faulty battery as well which is regulating an improper amount of current; also, if the vehicle is too old, the fuel pump relay might get damaged.


How do you test a fuel pump relay? How To Replace it?

Here is a step-by-step guide which you can go with to check the fuel pump relay of your car by yourself. Just follow the steps that are given below:

How do you test a fuel pump relay How To Replace it
How do you test a fuel pump relay? How To Replace it?
  • Step 1: Start by pulling out the fuel pump relay of your car; then, the location of the fuel pump relay will be where your foot is in the driver’s seat. Extract the fuel pump relay by removing the plastic covering by unbolting the screws using a screwdriver. Then remove the harness that is attached to it.
  • Step 2: Now, with the help of a battery and alligator cables, connect the 1st and 2nd hooks of the fuel pump relay’s 3rd and 5th hook to the multimeter to test its condition of it.
  • Step 3: turn on the multimeter, and if there is a sound as soon as you make all the connections, then it means that your fuel pump relay is working perfectly fine.

If you are not witnessing the same results, you should consider replacing the fuel pump relay as it is damaged.

For replacing the fuel pump relay, follow the same steps listed above to remove the fuel pump relay and then take a fresh fuel pump relay, connect the harness to it and then plug it back in the place where it was, at last, bolt the plastic covering carefully without damaging it.


How do you start a car with a bad fuel pump relay?

If you wish to start your car with a bad fuel pump relay, then here are some of the ways you can opt to do so:

How do you start a car with a bad fuel pump relay
How do you start a car with a bad fuel pump relay?
  • Fuel pressure gauge- Get a fuel pressure gauge from an automotive store; now attach it directly to the engine. After that, you can start your car as usual.
  • Heating the engine- you can also start your car with a faulty fuel pump relay by maintaining a constant heat of the engine.
  • Manual pressure- Generating a manual pressure in the engine can get your car to start normally, even if your car has a faulty fuel pump relay.

Can You Run A Car With A Bad Fuel Pump Relay?

Driving a car with any of its damaged parts depends on the level of damage it has undertaken. For example, if the damage is too great, you should not consider driving your car in this situation, and if the damage is somewhat less, then you can drive your car but make sure to check it so that you don’t exploit the safety measures.

Yes, a fuel pump relay can work intermittently. This usually happens because of loose connections between the terminals.


Frequently Asked Questions (fAQs)

How Much Does It Cost To Have A Fuel Pump Relay Replaced?

The average cost for replacing the fuel pump relay of your car is estimated to be $61 to $68, which is quite cheap if we compare it with the replacement cost of other fuel system parts.

How often Should You Replace Your Fuel Pump Relay?

This depends upon the time range and the distance covered by your car up till now, supposed if your car is into work for 15 years, then your should replace the fuel pump relay of your car as it might be damaged or wear out.

As for the distance of your car, if it has covered around 160,000 km to 300,000 km, then you should consider replacing your car’s fuel pump.

What Are The Causes Of Engine Misfiring?

There can be a lot of reasons for your car’s engine to misfire the most common among them is the fuel pump relay. Some of the other causes are as follows:
β˜‘οΈ Damaged spark plugs.
β˜‘οΈ Leakage in the head gasket.
β˜‘οΈ Faulty fuel injectors.
β˜‘οΈ Worn-out piston rings.

Conclusion:

The fuel pump relay is an important part of the fuel system in a car. Moreover, it is quite evident that it is not a serious issue that would end you up in a serious encounter, but an early repair can reduce the damage that your car is undertaking. So, I tried to answer the question can a bad fuel pump relay cause misfire, in a simplest way possible, I hope you found it helpful.