>> Engine check by means of the vacuum gage
Engine check by means of the vacuum gage
Using the vacuum gage, it is possible to receive information on a condition of the engine and to elicit the fact of violation of serviceability of functioning of a power supply system, damage of laying of a head of cylinders, piston rings, valves and so forth. Unfortunately, indications of the vacuum gage can be easily incorrectly interpreted, therefore the analysis of these measurements should be made taking into account the results of checks of the engine which are carried out by other methods.
At check are important both absolute values of indications of the vacuum gage, and speed of their change.
Basic provisions and fluctuations of an arrow of the vacuum gage at diagnostics of malfunctions of the engine
Connect the vacuum gage to the inlet pipeline. Start the engine and warm up it to normal working temperature.
Consider vacuum gage indications.
If the engine is in a normal state, indications of the vacuum gage should be stable and make 430-560 mm Hg.
Low stable indications of the vacuum gage can indicate the fact of destruction of laying between the inlet pipeline and the case of a throttle, damage of a vacuum hose, violation of installation of the moments of ignitions/phases of a gazoraspredeleniye.
If indications of the vacuum gage are unstable (arrow fluctuations) take place and are underestimated concerning norm by 80-200 mm Hg, it is necessary to check a condition of laying of the inlet pipeline near an entrance opening. The probability of failure of the corresponding injector is not excluded also.
Continuous falling of indications on 50-100 mm of mercury. rather stable value in high degree of probability points to damage of valves, - measure kompressionny pressure in cylinders.
Irregular falling of indications can speak about valve jamming, or failure in ignition.
If indications quickly fluctuate with amplitude about 100 mm Hg
at stable turns of idling, and on an exit of system of release the strong dymoobrazovaniye takes place, it is necessary to check a condition of directing plugs of valves.
Fast fluctuations of indications at increase in turns of idling, can be the certificate of damage of laying of the inlet pipeline and/or a head of cylinders, weakening of klapanny springs of valves, burn-outs of plates of valves, and also failures in ignition.
Insignificant fluctuations in a range of 25 mm of mercury. are usually connected with failures in ignition system.
If indications strongly fluctuate, probably, damage of laying of a head of cylinders, or walls actually the cylinder takes place.
Slow movement of an arrow in a wide range of values, is told about a contamination by system of operated ventilation of a case (PCV), damage of laying of the inlet pipeline, or laying between the case of a butterfly valve and the pipeline.
Check, vacuum gage indications after sharp and complete opening of a butterfly valve and its return to a starting position are how fast restored. If the engine is in a normal state, indications fall almost to zero, then increase approximately on 130 mm Hg above norm and again decrease to former values at stable turns of idling. If indications are restored slowly and pass through a maximum after butterfly valve closing, probably, piston rings are damaged. The long delay testifies to possible violation of passableness of system of release.