Symptoms of a Bad or Failing Carburetor

Before the advancement of computer controlled engine management systems, which came about in the late 70s, fuel and air was delivered into the engine mechanically through a component known as the carburetor. Carburetors are mechanical devices that blend fuel and air into a suitable mixture that can be ingested for internal combustion by an engine. While modern vehicles are no longer equipped with carburetors, they are still commonly found on many older road going cars and trucks, as well as classic and show vehicles. Since it is the component directly responsible for providing the fuel and air needed for the engine to run, the carburetor is one of the most important components on any vehicle equipped with one, and any problems with it can greatly affect the drivability and performance of the vehicle. Usually a bad or failing carburetor will produce a few symptoms that can alert the driver that attention may be required.

1. Reduced engine performance

One of the first symptoms commonly associated with a bad or failing carburetor is a reduced engine performance. The carburetor is the main component responsible for metering and delivering the air fuel mixture required for the engine to run. So if it develops any sort of issue, it can throw off this mixture and affect engine performance. A bad carburetor may result in an engine with sluggish acceleration, and a noticeable reduction in power and fuel efficiency.

2. Black smoke from exhaust

Another symptom commonly associated with a problematic carburetor is black smoke coming from the exhaust. Black smoke coming from the exhaust is an indicator that the engine is running excessively rich, or using too much fuel. A carburetor that is delivering excessive fuel to the point of producing black smoke, is not only burning unnecessary fuel, but also producing unnecessarily excessive emissions.

3. Backfiring or overheating

Engine backfiring and overheating are other common symptoms of a potential problem with the carburetor. If the carburetor has any sort of issue that results in it delivering a lean mixture, a mixture that does not have enough fuel, it may result in engine backfiring or overheating. Aside from causing backfire and overheating, lean mixtures are also bad for engine performance and in more serious cases can also result in damage to the engine.

4. Hard starting

Hard starting is another symptom commonly associated with a bad or failing carburetor. The air fuel ratio that the carburetor is responsible for blending and metering is especially important and sensitive during cold starts. If the carburetor has any sort of issue that disturbs the air fuel ratio it may result in hard starting. Depending on the exact nature of the issue, the vehicle may be hard to start, and get better as the engine warms up, or it may also be difficult to start even when warmed up.

While they are no longer standard, carburetors are still found on many road going cars and trucks, and are very important to the drivability and performance of the vehicles equipped with them. If your vehicle is displaying any of the symptoms above or you suspect that your carburetor may be having a problem, have the vehicle diagnosed by a professional technician, such as one from YourMechanic, to determine if your car needs a carburetor service or replacement.


Next Step

Schedule Vehicle Engine Mechanical Inspection

The most popular service booked by readers of this article is Vehicle Engine Mechanical Inspection. Once the problem has been diagnosed, you will be provided with an upfront quote for the recommended fix and receive $20.00 off as a credit towards the repair. YourMechanic’s technicians bring the dealership to you by performing this job at your home or office 7-days a week between 7AM-9PM. We currently cover over 2,000 cities and have 100k+ 5-star reviews... LEARN MORE

SEE PRICING & SCHEDULING

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Recent Vehicle Engine Mechanical Inspection reviews

Excellent Rating

(152,631)

Rating Summary
142,977
5,260
1,072
758
2,564
142,977
5,260
1,072
758
2,564

Peter

43 years of experience
1321 reviews
Peter
43 years of experience
GMC Sierra 1500 - Tune-up - Peoria, Arizona
Very professional, friendly and knowledgeable
Porsche Macan - Control Arm Assembly Replacement (Front Upper Left, Front Upper Right) - Scottsdale, Arizona
Peter is the best Mechanic ever. Thank you for such great service!

Chris

16 years of experience
298 reviews
Chris
16 years of experience
Hummer H2 - Oxygen Sensor Replacement (Rear/Lower/Downstream) - San Diego, California
A little late but excellent service had job done in about 20 mins.
Jeep Patriot - Battery - San Diego, California
very easy to coordinate with

Raymond

37 years of experience
241 reviews
Raymond
37 years of experience
Cadillac Brougham - Vehicle Engine Mechanical - Las Vegas, Nevada
Talent and passion for what you do in any field is critical, Raymond seems to have both. I have dealt with many Mechanics in my day Raymond is one of the best. Thank you sir.

Rusty

23 years of experience
448 reviews
Rusty
23 years of experience
GMC Sonoma - Vehicle Engine Mechanical Inspection - Arlington, Texas
Great overall impressions. Vechile is driveable and runs terrific now.

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

Related articles

Symptoms of a Bad or Failing Coolant Temperature Switch (Sensor)
Common signs include poor fuel economy, black smoke coming from the engine, engine overheating, and the Check Engine Light turning on.
How to Keep Your Car Running Well When It’s Hot Outside
Your Your car is affected considerably by the environment around it, including: Cold, freezing temperatures Dry, arid climates Hot temperatures and direct sunlight Precipitation in the form of rain or snow If your car is exposed to moisture...
What Causes a Car to Backfire?
You’ve got an image of it in your head right now. An old car drives off jerkily from a stop sign, tires screeching as...

Related questions

Vehicle overheating.

Hi there. This is a common problem. It is likely that a cooling system thermostat got stuck closed causing low flow through the cooling system and requires that it get replaced. It is also possible that there is a radiator...

Car is overheating

The cooling fan and thermostat would need to be checked for operation first. Also, the system pressure should be checked and tested for leaks. I recommend having a mechanic, such as one from YourMechanic, come out to you and inspect...

What is fail-safe cooling?

Your engine is equipped with a feature called fail-safe cooling. Essentially, this is a technology that helps minimize the damage caused by overheating the engine. If the engine begins to overheat, the Check Engine light will come on and the...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com