Why My Car Wont Go Faster Than 30MPH?

Are you wondering why your car wont go faster than 30mph? This could be due to the fact that your car has gone into limp home mode. Not everyone is a vehicle specialist and it can be rather frightening if your car begins to be odd for no obvious cause.

But it really is not that difficult to diagnose it. Thanks to cheap tools that you can buy these days, getting the codes has become very easy. Learn all the causes and their simple solutions in this article.

What Tool Do I Require To Diagnose Car Codes?

The automotive computer codes are saved in a car by the onboard computer diagnostic system (OBD). Hundreds of distinct codes can be actually represented by Check Engine Light. For this, an OBD scan tool is required. You can interface with your ECU and recover the issue codes from the scanner.

Some scanners can give information on the significance of the disclosed code, however, most will only give a combination of a five-digit number and a letter.

Steps To Fix Limp Home Mode

This problem of car wont go faster than 30mph is usually caused by ECUs when the automobile is in a limp-home. Limp mode is an automobile safety feature that operates when a defect is recovered by the motor or transmission control unit.

Once a fault is detected, the limp mode shut the automobile’s normal map and the car speed is lowered. Here are the steps to recover performance-

1. Connect An OBD Scanner

Your Engine Check Light is lit by one of your vehicle’s monitored systems when a defect is found. You must read the codes through the OBD port in order to figure out why the light is illuminated. An OBD scan tool is required. You can interface with your computer and recover the issue codes from the scanner.

Some scanners can give information on the significance of the disclosed code, however, most will only give a combination of a five-digit number and a letter.

2. Make Sure Car Battery Is Charged

Because the car has a low voltage battery condition, it is not possible to read all modules, impacting the quality and the exactness of the scan report. The vehicle battery has a low voltage status. Battery support is therefore needed when a vehicle is being scanned.

3. Dechiper The Codes

To use the scan tool, press READ CODES or select the READ CODES option in the tool menu. Some scanning devices might not automatically recognize the year of your vehicle or model. This information must first be entered before any issue codes are read by the scanning tool.

For example, P030X will be defined as the number of the misfiring cylinder if the misfire occurs in any specific cylinder. For instance, a P0302 code would warn you that the second cylinder is incorrect. The key aspect, however, is that the code does not tell the technician why the cylinder is misfired.

4. Perform Necessary Repairs


For example, the issue is with misfiring in the engine. To remove the plug, use a spark plug socket so that you can look at it well. The damage that you see helps you to establish the cause. If the plug is old, it can remedy the problem if it replaces it. Ensure that fresh spark plugs are replaced and split correctly.

5. Clear OBD Codes

Some vehicles automatically reset the problem codes causing the first error if the vehicle is activated and disabled three times in a row. Insert a key in the ignition, activate the vehicle for approximately a second, and then shut out for about a second.

Otherwise, with the help of the scanner, you can easily clear the trouble code in the car. 

Why Car Wont Go Faster Than 30mph In A Carburatted Car?

Increased altitudes signify reduced air density. If your car starts to act on sharp slopes and uphill, it could be the height. Bad gas may be packed with dirt and scrap that obstructs your pipes and filters. The fuel flow will be poor because of the obstruction or unclean jet. Maybe you may remedy this by applying a cleaning chemical for fuel injectors on your gas tank.

Can Mechanical Problems Cause Car Go Slow?

The catalytic converter can cause car wont go faster than 30mph problem. It prevents the right quantity of air from moving out of the motor if your catalytic converter is obstructed or is failing. On the other hand, a failing wheel bearing might generate vibration problems at much lesser velocities just to get worse with the speed of the vehicle.

Failure of wheel bearings will commonly sway back and forth whilst moving on the affected wheel. Sticky brakes can also create a lot of drag.

How Long Can You Drive With Limp Mode On?

Till it breaks indefinitely. The objective of the light and limp mode checking engine is to tell you that your engine is incorrect. It is not safe to drive your car limp and take it to a garage as fast as possible, for large amounts of time. Some individuals see limp mode as a disadvantage, stopping the correct functioning of their car and not giving it the way.

How Much Will It Cost To Fix Limp Mode?

Many car problems can cause the limp mode and can also lead to large repair expenditures. It will usually expect to have a cost of 50$ to 500$ to fix, but it can sometimes be much cheaper too. Most often, you can fix limp mode by replacing a part such as sensors or a connecting wire. In this case, expect to shell around 500$.


Limp mode is the number one cause of car wont go faster than 30mph. If your car is going into limp mode very often, then it can lead to serious damage to your car if you don’t get it fixed. So get it fixed as soon as possible to prevent any further implications. If you still have any doubts, then comment down below. 

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