Mechanics is a relatively Cartesian profession. But if there is indeed a problem that is sometimes difficult to explain, it is an unstable idle or loss of acceleration. Whether it's for a smart forfour, or any type of automobile. But we can help you understand. And yes, the reason can come from a lot of engine components, or even electronics. To detect the origin of the smart forfour failure, a fairly simple methodology must be followed. But first, let's see the signs of a slowdown idle.problem-idle-smart-forfour

Idle problem on a smart forfour: symptoms

Un unstable idle close to stall . This is truly the most recurrent idle dysfunction. This impression that the engine will stall while driving at a normal speed, or that the smart forfour grazes . It also happens that stalling occurs. In this case, it is a real danger for the motorist. In this case, don't wait too long to worry about it. We invite you to do your own checking via the paragraph below. We can also understand that the smart forfour has a acceleration malfunction . No longer reported in this case with idle malfunction. Losses of power and acceleration holes can happen for many reasons. These two phenomena should not be confused. We invite you to read our posts related to power losses.

smart forfour: develop a diagnosis to understand the origin of idling

You should start by performing various relatively easy checks, just before going into a little more detail.

Idle of the smart forfour: exhaust fumes.

A black smoke escapes from the exhaust. This usually means that the air and fuel mixture is out of order. But also that your air filter is clogged. In both cases, an idle malfunction can occur on this smart forfour. A White smoke escapes from the exhaust. In this case also it can come from a disturbance. White smoke is usually water vapor. It is therefore possible that it is a malfunction of the intake or of the cylinder head gasket.

Engine components check

As we said, an idle malfunction on this smart forfour could come from several points. You should therefore take the time to inspect the engine carefully. On the other hand, it is recommended to be very careful and not to touch the engine components too much, as this could amplify the breakdown or conceal the source of the malfunction. We naturally recommend that you go to a garage for a more suitable audit. Here are step by step the components to check.

  • The first thing to do is check all of the hoses . These can be perforated, or even detached.
  • In addition, the sensors and sensors of your engine. It is nevertheless difficult to check their correct functioning. You can find tutorials on youtube, and it usually requires electronic devices.
  • Perform a control of pressures hydraulic. Again, pressure testing requires appropriate equipment.

Idle worries are common however are complex to diagnose. A visual check on the smart forfour allows you to have a clearer vision, however it is wiser not to venture into amateur DIY.