Q: engine is shaking - 2006 BMW 325i

asked by on October 13, 2016

engine is shaking from time to time , with RPM up and down with less power for the car when its shaking. i replaced the coils and the spark plugs with no success , what should be the issue ? , i think it's an air issue...what you think ?

My car has 135000 miles.
My car has an automatic transmission.

Hello. This may be a sign of a failing idle air control valve. The idle air control valve is located on or near your intake manifold that monitors the air intake as it is mixed with fuel prior to being injected into the engine. This valve is controlled by the vehicle’s computer which will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage.

When you accelerate, the engine RPM increases, and as you let off the gas, the RPM slowly returns to the normal idling speed. However, when the engine RPM drops below the normal range of 800 RPM (for most cars), it is more than likely that you are dealing with an IAC valve problem. 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. A certified professional from YourMechanic can come to your location to diagnose the shaking issue and proceed with proper repairs.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Check engine light

This can happen occasionally for a variety of reasons and can sometimes be related to things that can change in the atmosphere such as air temperature and density for example. This can impact something like a throttle body temperature sensor....

AC blowing hot air after engine replacement

It sounds like your air conditioning has lost a charge. The refrigerant may have leaked, or they may not have charged the AC when they replaced the engine. I would have a technician come out and inspect your entire AC...

Shaking

Your engine has direct fuel injection. Over time, the intake valves can suffer from carbon build up because fuel is not being washed over them. Always use top tier gasoline even if you use Regular and not Premium. You can...

Related articles

Symptoms of a Bad or Failing Front Output Shaft Bearing
Common signs include a noisy drivetrain, excessive vibrations, and oil leaking from the transfer case in all-wheel or four-wheel vehicles.
Ten Sports Cars That Double as Good Daily Drivers
The best daily driver is a car that's reliable, usable, and still fun to drive. Popular daily sports cars include the BMW M3, Subaru WRX, and VW GTI.
A Buyer’s Guide to the 2012 BMW 7-Series
When When power, performance and luxury are at the top of your list, the 2012 BMW 7-Series is sure to be a perfect fit. From the stylish design to two length options for enhanced comfort, three available engines and two...