Signs of Bad Fuel Injectors: How to Tell if it’s Faulty, Leaky, Clogged or Dirty

In recent times, most automobiles, especially the models that date from 1980 to date, come complete with sophisticated electronic fuel...

In recent times, most automobiles, especially the models that date from 1980 to date, come complete with sophisticated electronic fuel injection engines that take the place of the old carburetors. The fuel injector constitutes a major component of this system and works to spray atomized fuel into the combustion chamber of an engine. Those of us that make use of a fuel injector cleaner on a regular basis may never experience problems, but sometimes, they might become clogged, dirty, or get damaged, which may call for a replacement. If you suspect that might be the case with your vehicle, read on to get the symptoms of damaged fuel injectors and much more.

 engine of the old car

Common Bad Fuel Injector Symptoms or Signs of Bad Fuel Injector

We have seen several symptoms that are indications of bad fuel injectors. They include;

  • Engine stalls or rough idle – Once your automobile fails to get enough quantity of fuel, or the fuel is unevenly supplied, it will cause the RPM to drop below its optimal level while idling, and the resultant effect is an uneven or rough violent idle. There may be the need to restart, if the RPM drops too low, causing the vehicle to stall.
  • Engine vibrates – When a fuel injector is faulty, the corresponding cylinder will be affected, and thus, it won’t be capable of firing. What this means is that while in motion, your engine is likely to hiccup, or vibrate in a bid to conclude each cycle without the needed fuel.
  • Engine misfires – When a clogged injector stops your engine from getting enough fuel, it is sure to misfire while in motion. It is either the automobile struggles to move, or you will experience a pause after stepping onto the gas pedestal. Whichever the case, you should arrest the situation on time to stop the engine from overheating or any other unforeseen problems that may result from there. This usually occurs when there is an upset of the proper fuel/air mix.
  • Check engine light comes on – This is one of the most noticeable signs of automobile issues when you suddenly see illumination from your “Check Engine” light on the dashboard. Though the sign may be a result of several problems, a bad fuel injector is among them. A car injector delivers less quantity of fuel than required, or in some cases more; it reduces the engine’s efficiency, and can even prompt the CEL to be on. This kind of situation can be confirmed with the use of an OBD2 scanner.
  • Fuel leak – Old age or damage can cause your fuel injector to crack or break, which may make it start leaking gasoline. In explanation, the fuel will no longer be able to get to the nozzle, but rather, it will be leaking from the body. A closer look at the fuel injector will reveal gasoline on the exterior or very close to the fuel rail. The leak often emanates from the fuel injector seal, resulting in the deterioration in the long run.
  • Fuel odor – This goes hand in hand with fuel leakage, but when your gasoline fails to burn due to faulty injector, or even one which is stuck open, the smell of gasoline will be high. Occasionally, the problem may be coming from your fuel lines, or a damaged sensor urging the ECU to inject extra fuel than necessary. However, it is important that you detect the cause of the odor and correct it. This stops the situation from turning into a huge safety hazard.
  • Engine surge – If excess spray of fuel is coming into the engine cylinder from the fuel injector, the resultant effect is a surge in the engine, slowing down your acceleration. While in motion, you will come to the realization that your engine RPM will alter to a great extent under constant load as opposed to staying at a constant RPM.
  • Bad fuel economy – Whenever the engine fails to get the right quantity of fuel for combustion, it demands additional fuel from the injector. The resultant effect of this is poor fuel economy, as the vehicle’s ECU believes that it needs more fuel than necessary.
  • Failed emission test – Increased emission is what you get when a leaking or broken fuel injector gives rise to an incomplete or uneven fuel burn. In several situations, a leak in a vehicle’s fuel injector can lead the fuel/air mix to become so rich that it burns out the car’s catalytic converter in the long run.

Clogged Fuel Injector Symptoms 

It may not be that easy to diagnose a clogged fuel injector as they are similar to bad coil, bad spark plug, or broken spark plug. Maybe one cylinder or more fails to fire. What causes clogging in fuel injectors or/ and their accompanying filter baskets is the presence of carbon, old fuel, and residue. You consider a fuel injector clogged when the quantity of gunk or debris within has built up so much that it hinders the free flow of fuel.

Once there is a clog in either the filer basket or the injector, the problem cannot be easily resolved no matter the quantity of fuel you inject or whichever fuel rail injector cleaner. The best way to deal with this is to take the injector out of the engine and clean it professionally.

Close up image of car engine

Dirty Fuel Injector Symptoms

You consider a fuel injector dirty when the additives and the hydrocarbons, which all constitute today’s fuels, together with carbon and engine gunk, results in restriction in the injectors. The flow rate of the fuel injector, distribution, and atomization will be impaired, and this gives rise to all forms of performance issues.

Though you can go ahead and get the best fuel injector cleaners for your car, the most efficient way to deal with this kind of problem is to remove the injector from the engine before cleaning it with the right cleaning equipment. More often than not, you don’t even need to buy a new injector; your old one can still suffice after it has been reconditioned to function at a similar level as a brand new one.

Leaking Fuel Injector

Important to note that sitting on a leaking fuel injector is a potential fire hazard and can bring on excess damages to your vehicle. Fuel injectors are known to develop holes as a result of old age, which makes the oil to be leaking out of the opening and onto the injector’s body. The seal, too, can also leak and will get worse with time.