Why can't a manual transmission car speed up when you step on the accelerator?

Sometimes, we need to overtake when driving on the road. If we overtake, we must speed up and continue to step on the gas. But sometimes, we step on the accelerator, but the speed does not increase, and even gets slower and slower. So what is the general reason for this situation?

Why does a manual transmission car not speed up after refueling?

When the accelerator pedal is pressed but the engine speed does not respond, it may be because the throttle valve cannot be opened and the air intake is insufficient.

Check if the throttle lever or the cable has any connection points that have fallen off, and then check if there is any gray hair blocking the air inlet, and if the air filter is too dirty. In general, the air filter will shake when refueling! When checking, you can temporarily disconnect the air filter for a short time and let the air in directly. If the fault is eliminated, it means that the air inlet is blocked.

If you can continue driving after downshifting, it means there is no major problem with the speed transmission and clutch transmission system.

Why can't the car speed up when you step on the accelerator?

Common reasons include:

Spark plugs need to be replaced

After the spark plugs have been used for a long time, the ignition will weaken, resulting in incomplete combustion of gasoline and weak acceleration! Replace the spark plugs on time, don't wait until the car can't start before changing them!

Spark plug replacement cycle: ordinary 30,000 to 40,000 km, platinum 50,000 to 60,000 km, iridium 70,000 to 80,000 km.

Insufficient fuel pump pressure

The fuel pressure of a car is 350kPa. If it is lower than 300kPa, you will not be able to add fuel while driving, and thus will not be able to increase the speed. You can replace the fuel pump!

Three-way catalytic converter is blocked

The faulty car makes a heavy sound when driving, refuels slowly, and the speed cannot reach 80 mph. It can be fixed by just cleaning it.

Crankshaft position sensor failure

The crankshaft position sensor is used to control ignition and fuel injection. If it is damaged, it will cause poor acceleration and even misfire.

What is the reason for the car's poor acceleration?

1. Fuel pump pressure may cause weak acceleration.

2. The fuel filter needs to be replaced. If it is not replaced for a long time, it may become clogged, making overtaking difficult.

3. Intake pressure sensor (air flow meter). Failure of this sensor can also cause poor refueling.

4. The fuel you add is not good. Nowadays, the gasoline in many small gas stations is not very good. Many drivers will find that their vehicles do not accelerate as well as before after adding gasoline.

5. The handbrake does not return to its original position. The handbrake lines of some vehicles may age after long-term use, causing the handbrake to fail to return to its original position, which may also lead to poor acceleration.