What Happens When the Intake Manifold Pressure Sensor is Damaged?
2 Answers
When the intake manifold pressure sensor is damaged, it will be unable to calculate air flow, resulting in issues such as no idle, weak acceleration, unstable engine operation, backfiring during rapid acceleration, and popping (due to either too lean or too rich air-fuel mixture). The ECU relies on three key components for its operation: the coolant temperature sensor, the intake pressure sensor, and the crankshaft position sensor. If the intake pressure sensor is damaged, the ECU loses accurate data on the intake air volume, leading to malfunctions. The intake pressure sensor, also known as MAP (Manifold Absolute Pressure), connects to the intake manifold via a vacuum hose. It senses changes in vacuum within the intake manifold as engine speed and load vary, converting these changes into voltage signals through internal resistance adjustments. These signals help the ECU adjust fuel injection and ignition timing. In carbureted or throttle body fuel-injected engines, the intake manifold refers to the pathway from the carburetor or throttle body to the cylinder head intake ports. Its function is to distribute the air-fuel mixture from the carburetor or throttle body to each cylinder's intake port. In port fuel-injected engines or diesel engines, the intake manifold solely distributes clean air to each cylinder's intake port. The intake manifold must distribute the air-fuel mixture or clean air as evenly as possible to each cylinder. To achieve this, the lengths of the gas flow paths inside the intake manifold should be as equal as possible. Solution for a damaged intake manifold pressure sensor: It is necessary to promptly visit a local 4S shop for inspection and repair.
As a seasoned driver with years of experience, I once encountered a faulty intake manifold pressure sensor, and my car immediately turned into a sick cat. At idle, the engine shook like it was dancing, and it lacked power during acceleration and uphill climbs—the acceleration felt sluggish. Fuel consumption also skyrocketed by nearly 20%, wasting a lot of money on gas. When the check engine light came on, a trip to the repair shop revealed that this sensor controls the air-fuel mixture ratio. Once it fails, the ECU starts messing with the fuel injection, leaving the engine 'underfed.' If left unfixed for too long, it can even damage the catalytic converter, doubling the repair costs. A simple habit like wiping the sensor during car washes to prevent dust buildup can save you a lot of trouble.
