What happens when the intake manifold pressure sensor fails?
3 Answers
Intake manifold pressure sensor failure symptoms: 1. Open or short circuit inside the sensor; 2. The sensor output signal cannot change with the variation of intake manifold vacuum; 3. The output signal voltage is too large or too small, deviating from the normal range; 4. Blockage or air leakage in the vacuum hose between intake pipes, or blockage of intake manifold vacuum ports. Additional information: The intake pressure sensor (Manifold-Absolute-Pressure-Sensor), abbreviated as MAP. It connects to the intake manifold via a vacuum tube, sensing vacuum changes in the intake manifold as engine speed and load vary. These changes are then converted into voltage signals through internal resistance changes in the sensor, which the ECM uses to adjust fuel injection quantity and ignition timing angle.
As a seasoned veteran in car repair, I've seen quite a few cases where the intake manifold pressure sensor fails. The engine starts shaking like a sieve, and acceleration becomes completely powerless, with the car moving frustratingly slow. Fuel consumption also skyrockets, turning a short trip into a long-distance expense that really hurts the wallet. The dashboard warning light often glows bright red, and sometimes the car won't even start, leaving you stuck and annoyed. The reason is simple: the sensor helps the computer measure air pressure, and when it fails, the fuel mixture goes haywire, causing the engine to run erratically. I always advise car owners to take it to a professional shop for repairs rather than trying DIY fixes, which could damage more components. Regular cleaning during maintenance to reduce carbon buildup can help prevent such issues. Periodic checks are good for both your wallet and safety.
I've been driving for over a decade, and recently my car's intake manifold pressure sensor failed - it felt exactly like this. The engine ran unevenly, making sudden knocking noises, and acceleration when pressing the gas pedal was as slow as a snail crawling, making overtaking absolutely nerve-wracking. Fuel consumption skyrocketed, calculating to dozens fewer kilometers per tank, significantly increasing expenses. The dashboard warning light kept flashing, and starting occasionally failed, especially on cold mornings. When the sensor fails, the computer gets confused, messing up the air-fuel mixture ratio. I drove straight to the repair shop to get it fixed - replacing the part brought much peace of mind. I recommend paying attention to these signs; addressing them early can save both money and time. When parking, remember to check the engine compartment and keep it clean to extend its lifespan.
