Mercedes-Benz 420SEL Car is slow to accelerate Inspection at your home or office.

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Car is slow to accelerate Inspection Service

How much does a Car is slow to accelerate Inspection cost?

On average, the cost for a Mercedes-Benz 420SEL Car is slow to accelerate Inspection is $95 with $0 for parts and $95 for labor. Prices may vary depending on your location.

CarServiceEstimateShop/Dealer Price
1989 Mercedes-Benz 420SELV8-4.2LService typeCar is slow to accelerate InspectionEstimate$114.99Shop/Dealer Price$132.49 - $145.62
1991 Mercedes-Benz 420SELV8-4.2LService typeCar is slow to accelerate InspectionEstimate$94.99Shop/Dealer Price$112.52 - $125.67
1988 Mercedes-Benz 420SELV8-4.2LService typeCar is slow to accelerate InspectionEstimate$94.99Shop/Dealer Price$112.52 - $125.67
1990 Mercedes-Benz 420SELV8-4.2LService typeCar is slow to accelerate InspectionEstimate$94.99Shop/Dealer Price$112.48 - $125.60
1987 Mercedes-Benz 420SELV8-4.2LService typeCar is slow to accelerate InspectionEstimate$94.99Shop/Dealer Price$112.55 - $125.72
1986 Mercedes-Benz 420SELV8-4.2LService typeCar is slow to accelerate InspectionEstimate$94.99Shop/Dealer Price$112.52 - $125.67
Show example Mercedes-Benz 420SEL Car is slow to accelerate Inspection prices

A car that is getting fuel and is properly tuned should take off quickly when the accelerator is pressed. A vehicle that is sluggish or slow to accelerate can be dangerous, especially at intersections and on-ramps.

Modern cars have a very complex system that delivers fuel to the engine and rids of the vehicle of exhaust gases. A failure in any part of this system can lead to a car that is slow to accelerate. In the majority of cases, the problem can be traced back to the fuel system.

A vehicle that is slow to accelerate should be repaired immediately as it can be dangerous to drive.

How this system works:

The fuel system is responsible for supplying fuel to the engine. Fuel is mixed with air, atomized and vaporized in the intake system, which provides power to drive the pistons of the engine. There are a variety of different fuel system types but most of them have the same basic parts.

The fuel tank stores the gasoline. Fuel is pulled through the fuel lines by the fuel pump and is fed into the fuel injectors. Older cars have a carburetor and throttle body injectors instead of fuel injectors. The fuel injectors spray gasoline into the cylinders where it is mixed with air and then ignites during the compression stage. The result is an explosion that moves the pistons.

Common reasons for this to happen:

  • Bad or Clogged Fuel Injector: Fuel injectors can become clogged due to contaminates in the fuel. Fuel injectors, by their very nature, must be very precise in controlling the amount of fuel that goes into the combustion chamber so they have very small passages that deliver the fuel. Over time these tiny passages will become clogged which impedes the delivery of fuel.

When an injector is clogged it can degrade the performance of the vehicle and the car may accelerate slowly or feel that it does not have enough power. Other symptoms include a rough idle, a vehicle that is hard to start and a decrease in fuel efficiency.

  • Defective Fuel Pump: The fuel pump pulls the fuel from the gas tank to the engine via the fuel lines. If the pump stops working, malfunctions, or becomes clogged, it will not supply enough fuel to the injectors. This can cause the vehicle to accelerate slowly, or even sputter and stall, especially at high speeds.

  • Clogged Fuel Filter: The job of the fuel filter is to filter out containments in the fuel and if it becomes clogged it can restrict the amount of fuel that reaches the injectors. This can cause a vehicle to accelerate slowly. Fuel filters are designed to be replaced on a regular basis.

  • Dirty Airflow Sensor: This part detects the mass of air that enters the fuel injection system and hands that information off to the engines’ computer which allows the computer to deliver the proper amount of fuel to the air. These sensors can become dirty or malfunction over time, which results in the wrong data being sent to the computer. A slow accelerating car is the result of this incorrect data. It may also trigger the Check Engine light.

  • Leaking Fuel Line: A leak in the fuel line will drain off enough fuel that it leaves a shortage for the injectors. This not only affects the performance of the car but will also create a dangerous situation. If you smell gasoline in the vicinity of the car or see a puddle of fuel underneath the vehicle, the car should be inspected and repaired immediately.

  • Vacuum Leak: A leak in the vacuum system can affect the ability of the car’s computer system to properly regulate the fuel to air ratio. One of the major symptoms of a vacuum leak is a car that is slow to accelerate or feels like it has a lack of power. In addition the check engine light will probably illuminate.

  • Failing Catalytic Converter: A failing or clogged catalytic converter will prevent the proper amount of air from going into the engine. In most cases the vehicle will run hotter than normal, will accelerate slowly and feel like there is a loss of power. Issues with the catalytic converter tend to be fairly expensive repairs.

What to expect:

A top-rated mobile mechanic will come to your home or office to determine the source and cause of the car is slow to accelerate issue, ​and will then provide a detailed inspection report that includes the scope and cost of the necessary repairs.

How it's done:

The mechanic will check your car's fuel system for leaks and any defective parts. This includes fuel injectors, fuel pump, fuel filter, airflow sensors and other important components related to the vehicle's slow acceleration. It may be necessary to test drive the car in order to verify the acceleration issue and provide an accurate diagnosis.

How important is this service?

A car that accelerates slowly is a dangerous vehicle to drive, especially at intersections and on ramps. Failing to fix simple fuel system problems will often lead to a more expensive repair down the road and eventually a car that may not run at all. A slow accelerating car should be inspected and repaired as soon as possible.

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Excellent Rating

(18)

Rating Summary
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Marco

29 years of experience
222 reviews
Marco
29 years of experience
Mercedes-Benz 420SEL V8-4.2L - Neutral Safety Switch - Riverside, California
A life-saver

Patrick

33 years of experience
1412 reviews
Patrick
33 years of experience
Mercedes-Benz 420SEL V8-4.2L - Car is not starting - Pflugerville, Texas
Very good.

Carlos

28 years of experience
502 reviews
Carlos
28 years of experience
Mercedes-Benz 420SEL V8-4.2L - Alternator Repair - Riverside, California
Carlos is chill dude; showed up early and helped me out in under an hour. He also gave me tips on how to become a mechanic. Honestly will book him again if anything happens.

Christian

22 years of experience
68 reviews
Christian
22 years of experience
Mercedes-Benz 420SEL V8-4.2L - Check Fuel System - Hayward, California
Very professional and very knowledgeable!look forward for him working on my car in the future

Excellent Rating

(18)

Rating Summary
17
0
0
1
0
17
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0
1
0
Number of Mercedes-Benz 420SEL services completed
198+
services done by our mechanics
TOTAL NUMBER OF EXPERT Mercedes-Benz MECHANICS
1100+
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