13 is250 tachometer is unstable.

13 is250 tachometer is unstable, which may be caused by uneven air intake or oil supply and carbon deposition, resulting in unstable performance, vacuum tube falling off or air leakage.

Check the idle switch, turn on the air conditioner or turn the steering wheel when idling. If the engine speed does not increase, there is something wrong with this place. Adjust, repair or replace the throttle position sensor.

Check the intake pipe directly by listening to the sound of the intake pipe. If there is a leak, it means that there is a leak in the air intake system. Find leaks, reseal or replace related parts.