Symptoms of a Bad or Failing Fuel Filler Cap

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Cost of Replacing a Bad or Failing Fuel Filler Cap

Common signs include the cap not tightening properly, a fuel smell in the car, and the Check Engine Light coming on. Our certified technicians can come to you and diagnose the problem. You will receive a $30 credit towards any follow-up repairs that result from the diagnostic. Following are example prices for Fuel Filler Cap Replacement. Click on the button below to get an upfront quote for your car.

Cars Estimate Parts Cost Labor Cost Savings Average Dealer Price
2006 Chevrolet Express 2500 $91 $20.80 $70.00 29% $128.30
2007 Chevrolet Optra $87 $17.28 $70.00 30% $124.78
2010 Toyota 4Runner $85 $15.47 $70.00 30% $122.97
2015 Mercedes-Benz C400 $103 $32.77 $70.00 26% $140.27
2010 Land Rover Range Rover $138 $68.38 $70.00 21% $175.88
2013 BMW M6 $113 $43.18 $70.00 24% $150.68
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How to Diagnose a Bad or Failing Fuel Filler Cap?

fuel filler cap

The gas cap is a very simple, but important component that is found on the vast majority of road going vehicles. It’s purpose is to ensure that no dirt, debris, or dust enter your fuel tank, and that none of the fuel vapors escape. The gas cap plays an important role in the proper operation of the vehicle’s evaporative emissions system, which is designed to trap and reuse fuel vapors that would otherwise be released into the atmosphere. As the gas cap is removed every time the vehicle is refueled, it will often wear out simply due to repeated use. While a faulty gas cap will not necessarily cause major performance issues, it can cause the vehicle to experience fuel and emission problems. Usually a bad or failing gas cap will produce a few symptoms that can alert the driver of a potential problem.

1. Cap does not tighten properly

One of the first symptoms of a bad or failing gas cap is a cap that does not tighten properly. Most fuel caps have a built in mechanism that will cause them to click once they are adequately tightened. If when tightening the cap, it does not eventually click, or pops loose after it clicks then that is a sign that the cap may be damaged and need to be replaced.

2. Fuel smell from the vehicle

Another symptom of an issue with the fuel cap is a fuel smell from the vehicle. If the gas cap leaks, or fails to provide a proper seal it can cause fuel vapors to escape from the fuel tank, which may cause the vehicle to give off a fuel smell. A fuel smell can also be caused by various other issues, so a proper diagnosis is recommended if you are unsure.

3. Check Engine Light comes on

Another common symptom of an issue with the fuel cap is an illuminated Check Engine Light. If the fuel cap has any issues sealing the fuel tank it can cause the Check Engine Light to come on for evaporative emissions system reasons. The vehicle’s evaporative emissions system is designed to trap and reuse fuel vapors, and can detect if there is a leak in the system. A leaky fuel cap will compromise the effectiveness of the evaporative emissions system, and as a result will set off the Check Engine Light to notify the driver of the issue. A Check Engine Light can also be set off by a wide variety of other issue so having the computer scanned for trouble codes is highly recommended.

While a faulty fuel cap probably won’t cause any major drivability issues with the vehicle, it can cause the Check Engine Light to illuminate. If you suspect that your gas cap may be having an issue, have the vehicle inspected by a professional technician, such as one from YourMechanic, to determine if the cap should be replaced.

Gas Cap
fuel system

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Recent Fuel Filler Cap Replacement reviews

Excellent Rating


YourMechanic Fuel Filler Cap Replacement Service

Average Rating

4.7/5

Number of Reviews

9

Rating Summary
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David

13 years of experience
339 reviews
David
13 years of experience
I was happily surprised when the check engine light stayed off. I think David did an excellent job.
2003 DODGE DAKOTA - FUEL FILLER CAP - NORTH HIGHLANDS, CALIFORNIA

Jay

34 years of experience
566 reviews
Jay
34 years of experience
He was very trustworthy and knowledgeable, and was able to effectively explain to me (a person who knows very little about cars) what was going on with my car and why it was happening or why it's something I need to pay attention to. I definitely would trust him to work on my car again in the future.
2010 DODGE GRAND CARAVAN - FUEL FILLER CAP - ALTA LOMA, CALIFORNIA

James

27 years of experience
373 reviews
James
27 years of experience
Very nice young man. Did a great job!
2004 FORD ESCAPE - FUEL FILLER CAP - OVIEDO, FLORIDA

Clarissa

24 years of experience
108 reviews
Clarissa
24 years of experience
Clarissa has been the best mechanic. No unneeded parts or services were pushed. Everything was explained as the process went on. I highly recommend!
2003 HYUNDAI XG350 - FUEL FILLER CAP - PHILADELPHIA, PENNSYLVANIA

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