Why does my car idle up and down when I start it?

Among the potential underlying causes are vacuum leaks, EGR system malfunctions, malfunctioning oxygen sensors, dirty fuel injectors, fuel pump malfunction, faulty spark plugs, a faulty mass airflow sensor, or a faulty throttle position sensor.

Why does my car drop in rpms when idling?

This may be a sign of a failing idle air control valve. In cases where this valve is clogged or is failing, your vehicle will stall instead of slowing to an idle after the release of the throttle. I recommend having a professional replace your idle air control valve.

Why does my Acura TSX shake when accelerating?

A misfiring engine is one of the most common reasons your TSX will shake when accelerating. A vehicle’s ignition system consists of spark plugs, coil packs, and maybe plug wires. If any of these ignition components fail to deliver enough spark, your vehicle will experience a misfire.

Why is my idle fluctuating?

Erratic engine idle can be caused by various factors, but the most common and likely cause is a dirty or malfunctioning Mass Air Flow (MAF) sensor. This is a device found in fuel-injected cars and measures air flow so that the appropriate amount of fuel can be injected.

Why does my car engine shake when I accelerate?

One reason your car could be shaking with acceleration is that the engine’s mounts are broken. If even one of the motor mounts is broken, this could occur, and puts more stress on the remaining mounts. Replacing broken motor mounts is one way to stop vibration during acceleration.

Why does my Acura TL shake?

Any unusual shaking or vibrating forces coming from the engine is cause for concern. It could be something as simple as old spark plugs producing an uneven power delivery, it could be something serious like worn or broken engine mounts, or it could be even more serious in the case of internal engine damage.