What's wrong with Santana's cold car idling less than 1 100?

There were superman cars in Santana era. When the car is cold, the idle speed shakes, and the hot car is normal.

Troubleshooting:

The problem of the car is obvious, that is, the machine is idling when it is cold, which is also a common problem in the use of users. First, check whether the speed value is too low when the cold car is idling (standard 1000- 1200r/min).

, because too low speed is easy to cause engine idling jitter. If the engine speed is too low when the engine is cold, please find out the cause of the problem. If the throttle is not dirty, brush the side of the throttle to check whether the idle speed control motor is effective. The inspection method is as follows:

If the idle switch contacts are closed, check whether the idle switch contacts are open when the accelerator pedal is depressed. If the idle speed control motor is replaced, basic settings should be made (the so-called basic settings mean that the engine control unit and the throttle control part are matched, and if the engine control unit is powered off, basic settings must be made).

Remove the intake manifold and check the intake valve for serious carbon deposition. Because too much carbon deposit on the valve will inevitably lead to the valve closing is not strict, the mixture is too thin, and the uneven work of the four cylinders will cause idling jitter. Similarly, check whether the hydraulic tappet works well, because the oil pressure is too high when the machine is cold, which has obvious influence on the working lift of the hydraulic tappet. If there is a hydraulic tappet with poor work, the cylinder-missing state will definitely exist, and the idle speed value will be reduced, resulting in idle speed jitter of the cold machine.

Don't easily repair the engine without a clear diagnosis of the external electrical components, so as not to cause economic losses.