Having a MAP sensor in a car doesn’t mean it will last forever. With use, it can get dirty, clogged or spoilt and needs to be replaced. In that case, replacing the MAP sensor would be the best solution. But the question is, what to do after replacing MAP sensor?
After replacing the MAP sensor, you should use an OBD scanner to reset the car’s ECU to start getting fresh reading from the new MAP sensor. Failure to reset the ECU, the car will continue to use readings from the old sensor until you complete a drive cycle.
Can You Replace a MAP Sensor?
Yes, a car’s MAP sensor can be replaced when it has gone bad and starts giving incorrect readings to the car’s computer, hence causing the car to misfire, loose power, and consume more fuel.
What to Do After Replacing MAP Sensor
There are several things to do after replacing a MAP sensor, They are:
1. Reconnect the Battery
Before replacing a MAP sensor, it is recommended to have your battery disconnected before starting the replacement. However, when the replacement is completed, the first thing to do is to reconnect the battery.
Be that as it may, before reconnecting the battery, ensure that the job is completed. Its not wise to replace a mass air flow sensor or MAP sensor with a connected battery.
2. Recheck all the Connections
Failure to connect all the connectable parts of the MAP sensor to their components can have severe effects to the engine. Therefore, ensure that all the connections are properly connected to the right source.
3. Reset the Car’s ECU
After the replacement is completed and the connections checked, the next step would be to reset the car’s computer to start getting fresh readings from the just installed sensor.
There are several reasons why this should be done. If you fail to reset or reprogram the car’s ECU and start driving the car, the car will continue to function with the readings from the old sensor.
You will probably need to complete a drive cycle for the computer to reset itself and starts getting readings from the new sensor. Moreover, for you to complete a drive cycle, you need to drive for about 50 to 100 miles and sometimes more depending on your kind of car. So, its better to reset the car’s ECU to start using the new sensor.
4. Drive and Observe the Car
After the reset is done, you are free to drive the car. However, disconnecting the battery before installing the new MAP sensor will help remove the check engine warning light that must have appeared because of the bad sensor.
If the battery disconnection did not clear the warning, resetting the car’s computer would clear the code as well as the check engine light.
However, while you drive the car, observe and see if the check engine light comes back on again. If it does, have it scanned and if the code reads the same MAP sensor issue, then it could be that there’s something wrong with the just installed sensor or the connections .
Nonetheless, the car should be able to run fine after the sensor is replaced with a good one. All those symptoms you experience when the bad sensor was in use will disappear immediately the reset is done.
How to Reset MAP Sensor
There are three known ways to reset a MAP sensor: They are:
By Disconnecting the Battery
Disconnecting the battery is a proven way to reset the MAP sensor. All you have to do is to:
- Find where the car battery is located (Some batteries are placed inside the hood while some are located in the boot)
- Once you find the battery, disconnect the negative terminal of the battery (While doing this ensure not to place the battery connections to any metals to avoid any possible spark. Also, do not remove the positive terminal to avoid causing a spark when the connections touches any metal. Better still remove all the terminals or just have the negative battery terminal removed)
- After the battery is disconnected, allow it to sit for 30 minutes. If you have more time, you can allow it to sit
- After 30 minutes to an hour, reconnect the battery and tighten it properly
Doing this should be able to reset the MAP sensor. With that being said, if you removed the battery before replacing the MAP sensor, allow the car to sit for 30 minutes to an hour before reconnecting the battery to clear all the error codes that are associated with the old sensor.
By Using an OBD Scanner
This method is only possible if you have the OBD scanner tool with you or you prefer to pay some money to those that have the scanner to have them clear the code for you.
They should be able to connect the scanner to the car, reads the codes associated with the MAP sensor, and clear the code. If the newly installed sensor is in good condition, the error code will be gone and would not reappear again.
By Completing a Drive Cycle
You can also reset the MAP sensor by driving the car. After the sensor is replaced, you can take the car for a drive. While you drive your car, the car will perform a self diagnostic test.
If after the test, it comes back that the new sensor is giving the correct readings, the code will clear itself and the car will start driving well.
However, this method is not recommended. First of all, you should have your battery removed while replacing a MAP sensor, allowing the car to sit for 30 minutes is enough to clear whatever code the old sensor left in the car. So, you don’t need to start driving your car to reset the sensor.
Why is My New MAP Sensor not Working?
Your new MAP sensor is not working because:
- You Installed a Wrong Map Sensor: If you bought and installed a wrong MAP sensor in your car, it can cause it not to work the way it should. When purchasing a replacement part, you should endeavor to purchase one that has the exact part number with the one in your car. The fact they all look alike doesn’t mean they’re all interchangeable.
- The New Sensor is Bad: Its also possible that the newly installed sensor is bad. If the sensor is made of inferior material, it might not work the way it should. For example, I’ve bought new spark plugs for my car in the past and it failed after driving for 10 miles because the plugs were made of inferior material. So, check the brand that made the sensor before making your purchase.
- Clogged Hose: If the MAP sensor in your car uses a hose, it could be that the hose is clogged, thereby preventing the sensor from giving the correct readings to the ECU.
- Leaking Hose: The same goes to a leaking hose. If the hose is leaking, the sensor will not be able to give the car’s computer the right readings needed from it.
- The Computer is not Reprogrammed: As reiterated earlier, once you’re done replacing the MAP sensor, the next thing to do is to reset the car’s computer to start getting readings from the new sensor. Until the reset is done, the computer will continue to use readings from the bad sensor pending when you complete a drive cycle.
Final Thoughts
Like I’ve always said, not all parts of the car are meant to last forever. Some will get bad as time goes on and when this happens, the best solution would be to have them replaced.
When the MAP sensor of your car goes bad and you replaced it with a good one, you are obligated to reset the car’s ECU in order to start using readings from the new sensor.
Failure to do this, you will continue to drive with readings from the old sensor until you complete a drive cycle whereby the car’s computer resets itself.