Aveo Manifold Pressure Sensor Vacuum Leak

Interesting symptoms. The manifold pressure sensor, also known as the MAP sensor, is certainly a prime suspect given the confluence of issues you're describing. A large vacuum leakage can indeed cause the sensor to report incorrect values, leading to the ECU miscalculating the air-fuel mixture. Before condemning the sensor outright, have you inspected the vacuum lines connected to the intake manifold for any signs of cracks, looseness, or damage? Consider it like checking the pipes in your house before calling a plumber for a leak - sometimes it is an easy fix. Also, do you have access to an OBDII scanner to read the specific error code? That would greatly assist in pinpointing the problem.

Thanks for the quick reply! I haven't actually checked the vacuum lines myself yet, admittedly. I was hoping it would be something simple like that. Regarding the OBDII scanner, I do have one. It's throwing a P0106 code – Manifold Absolute Pressure/Barometric Pressure Range/Performance Problem. Does that solidify the pressure sensor as the likely culprit, or could it still be something else?

The P0106 code, coupled with your symptoms, strongly suggests an issue with the manifold pressure sensor or the associated vacuum system. Given that you suspect a vacuum leak and the code points to a performance issue within the MAP sensor's range, I would advise against replacing the sensor immediately. It's like replacing a lightbulb when the fuse is blown. While the sensor might be faulty, the underlying cause is likely the vacuum leak. However, diagnosing vacuum leaks without specialized equipment can be challenging. Therefore, I recommend taking your Aveo to a trusted mechanic for a thorough inspection. They can perform a smoke test to identify any leaks in the intake manifold and vacuum lines. This approach will provide a more definitive diagnosis and prevent you from unnecessarily replacing a potentially functional sensor.

Appreciate the detailed advice. You nailed it. Took it to the shop, and as you suspected, a large vacuum leak was the culprit, causing the sensor to go haywire. They located and fixed the leak, replaced the faulty sensor, and all is well. Total cost was around 235€.