Lexus GS400 Car is getting worse gas mileage Inspection at your home or office.

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Car is getting worse gas mileage Inspection Service

How much does a Car is getting worse gas mileage Inspection cost?

On average, the cost for a Lexus GS400 Car is getting worse gas mileage Inspection is $95 with $0 for parts and $95 for labor. Prices may vary depending on your location.

CarServiceEstimateShop/Dealer Price
1998 Lexus GS400V8-4.0LService typeCar is getting worse gas mileage InspectionEstimate$114.99Shop/Dealer Price$132.49 - $145.62
1999 Lexus GS400V8-4.0LService typeCar is getting worse gas mileage InspectionEstimate$94.99Shop/Dealer Price$112.52 - $125.67
2000 Lexus GS400V8-4.0LService typeCar is getting worse gas mileage InspectionEstimate$94.99Shop/Dealer Price$112.52 - $125.67
Show example Lexus GS400 Car is getting worse gas mileage Inspection prices

Poor gas mileage, especially a sudden drop in fuel efficiency, can be blamed on a number of issues. It can also be an indicator of a much more serious issue that if left un-repaired, can develop into an expensive repair.

There are dozens of problems that can lead to a drop in gas mileage, some of them are serious and some can be easily corrected. Here are some of the more common issues that can affect the fuel efficiency of most cars.

How this system works:

The fuel system stores and supplies fuel to the car to help drive the engine. Fuel is mixed with air, atomized and vaporized in the engine intake system. It is then compressed in the engine cylinder and ignited which produces energy to move the pistons. There are different engine layouts and designs but most of them work in the same basic way.

When the system is working as designed, and under certain conditions, maximum fuel efficiency will be achieved. Numerous factors can have an affect on fuel efficiency so it is usually a constantly changing number but a serious and sudden drop in miles per gallon is cause for concern and the vehicle should be inspected.

Common reasons for this to happen:

  • Dirty Oxygen Sensor: An oxygen sensor measures exactly how rich or lean the exhaust gases are when they leave the combustion chamber. The data is used by the vehicle computer to adjust the amount of fuel entering the engine. If the sensor is dirty or failing it can lead to a drop in miles per gallon. It can also lead to failed emission tests and a rough idle.

  • Dirty Fuel Injectors: Fuel injectors spray fuel into the cylinders where it is mixed with air and ignited. Over time the fuel injector system can become clogged. This can lead to a drop in fuel efficiency as well as slow acceleration and the car not having enough power. If caught early, simply cleaning the injectors can solve the problem. As it progresses, the injectors may have to be replaced.

  • Bad or Dirty Spark Plugs: Spark plugs ignite the fuel in the combustion chamber. If they are dirty or working incorrectly, it can cause the engine to misfire, leading to poor engine performance. This can lead to a lack of power as well as a big decline in fuel efficiency.

  • Malfunctioning Mass Airflow Sensor: A mass airflow sensor detects the amount of air coming into the fuel injection system. It delivers that information to the vehicle's computer, which crunches the numbers and then delivers the proper amount of fuel to the air in the vehicle. A dirty airflow sensor will degrade fuel efficiently and lead to a rough idle and even stalling as the problem progresses.

  • Misaligned Tires: Tires that are low or out of alignment can lead to a drop in fuel efficiency. Checking the tire pressure and have the alignment checked on regular basis can help prevent this problem.

  • Defective Fuel Pump: Fuel delivery issues can drastically affect fuel efficiency. The fuel pump pulls fuel from the gas tank to the fuel injectors. The fuel pump can become clogged or malfunction. A bad fuel pump can lead to a rough running engine because it is not getting enough fuel. This will lead to a decline in gas mileage. If this issue is not addressed it will lead to a rough, idle, sputtering and stalling.

  • Clogged Fuel Filter: A clogged fuel filter will also cause problems with gas mileage. The fuel filter screens out contaminants in the fuel, and over time it will become clogged. Fuel filters need to be replaced periodically.

  • Stuck Brake Caliper: A stuck caliper on a disc brake or a stuck shoe on a drum brake can lead to a serious decline in gas mileage. In addition, any brake issue can make the vehicle dangerous to drive. If the decline in efficiency is accompanied by the vehicle pulling to one side, the brake system should be inspected immediately.

What to expect:

A top-rated mobile mechanic will come to your home or office to determine the source and cause of the poor gas mileage issue and will then provide a detailed inspection report that includes the scope and cost of the necessary repairs.

How it's done:

A mechanic will inspect your fuel injectors, spark plugs, airflow sensor, tires and other important components to reach an accurate diagnosis. It may be necessary for the mechanic to test drive the car to produce acceptable results and pinpoint the source of the problem.

How important is this service?

A few of these issues are easy to fix but others are an indicator of a much more serious problem. Issues related to the fuel system will eventually lead to a rough running engine, stalling, and a car that won’t start at all.

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Real customer reviews from Lexus owners like you.

Excellent Rating

(34)

Rating Summary
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Daniel

21 years of experience
346 reviews
Daniel
21 years of experience
Lexus GS400 V8-4.0L - Coolant is leaking - Houston, Texas
Daniel was great he took the time to Listen to me.. Being that I had a uncomfortable experience with someone else...He explain to me the necessary steps I would have to make as well as he would make.. Not to mention he also has a great sense of humor.. I would recommend him to my family and friends.. Thanks again Daniel for Listening that is very important with me... See you soon

Anthony

35 years of experience
19 reviews
Anthony
35 years of experience
Lexus GS400 V8-4.0L - Oil Change - Danville, California

Chris

16 years of experience
122 reviews
Chris
16 years of experience
Lexus GS400 V8-4.0L - Inspection / Diagnostics - Los Angeles, California
While AAA essentially diagnosed and fixed the (immediate) problem with my vehicle, Chris followed up with a more thorough inspection of my engine, brake pads, and tires. There is only so much you can check on without the car being pulled to a station or a shop, however Chris did ALL that he could while he was there servicing my vehicle. Aces across the board!

Nathan

29 years of experience
260 reviews
Nathan
29 years of experience
Lexus GS400 V8-4.0L - Alternator - Jenks, Oklahoma
After having my car sit in my garage for a month with a dead alternator, I found yourmechanic.com, and more specifically, Nathan Thorne. YourMechanic.com's website was super easy to use, they already had the repair I needed in their system, gave me an exact quote, and let me pick when the repair was going to happen. Now the best part. When the mechanic came out, he determined that the repair was going to take significantly longer than they had quoted...AND DIDN'T UPCHARGE ME. He just did the repair and said since the company's quote on the time for the repair was wrong, he would just deal with them. Couldn't have asked for better service and will definitely recommend and use Nathan Thorne again.

Excellent Rating

(34)

Rating Summary
33
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Number of Lexus GS400 services completed
374+
services done by our mechanics
TOTAL NUMBER OF EXPERT Lexus MECHANICS
1100+
experts on our platform

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