Abstract
ABSTRACT:
Incomplete combustion determined by the improper technical state of the engine components causes it's specific behavior, with abrupt functioning and brutal response to deceleration (surge, stumble, hesitation and rough).
Establishing the exact cause that determines the difficult running of the engine suppose high costs for diagnoses and additional costs for repair the damages.
To reduce costs related to diagnoses it is required that to be done with specific instruments, connected to the central computer of the car. This should be done only after removal all another external possible causes that are easier to spot.
After connecting to the measurement instruments of pollution exhaust we can determine the first cause that determines the increase of exhaust - air filter. If it's replacement doesn't modify the results we have to verify if the vacuum equipment is functioning correctly, because a deteriorate membrane or valve can induce abrupt functioning of the engine.
If all this preliminary tests doesn't offer any hints then the specific diagnoses instruments should be use. Should be checked if the computer gives any information regarding the abnormal running of engine. If an error code is present then specific measure should be taken base on this. If the computer doesn't offer any information then each component that determines the pollution should be checked.
The depression from admission collector is checked to be higher then the value provided by the manufacturer. The oxygen sensor should be checked.
The sensor that controls the admission air should be checked (resistance, tension and cleaning state). If there are no problems we should go to the next step, the checking of the sensor that monitor the throttle position with tension measurement in both situations - idle and total admission. We will proceed to unplug the injectors or sparking plugs one by one and the engine behavior is watched. If for each cylinder unplugged the engine has the same behavior then the lubricate installation pressure is checked.
If these checks don't succeed we have to change the ECU.