|
我從手冊抓了一段有關真空值的真空測試,可以用真空值得知目前的引擎狀況
晚點有空會翻成中文,先看一下
可能翻的不是很好.....歡迎指正
1.NORMAL READING: Needle between 51-74 kPa (15-22 in-Hg) and holding steady.
正常讀數: 指針穩定在 38.1 ~ 55.88cm-Hg
2.NORMAL READING DURING RAPID ACCELERATION AND DECELERATION: When the engine is rapidly accelerated (dotted needle), the needle will drop to a low reading (not to zero). When the throttle is suddenly released, the needle will snap back up to a higher than normal figure.
極加減速的正常讀數: 當引擎急加速 ,指針會有低數值(不是0),當油門突然放開時,指針會回到比正常值還高一點.
3.NORMAL FOR HIGH-LIFT CAMSHAFT WITH LARGE OVERLAP: The needle will register as low as 51 kPa (15 in-Hg) but will be relatively steady. Some oscillation is normal.
有大重疊且高揚程凸輪軸的正常值: 指針可能低到 38.1 cm-Hg,但有相對比例的規律. 有些震動是正常的.
4.WORN RINGS OR DILUTED OIL: When the engine is accelerated (dotted needle), the needle drops to 0 kPa (0 in-Hg). Upon deceleration, the needle runs slightly above 74 kPa (22 in-Hg).
墊圈磨損或機油變稀: 當引擎加速時,指針掉到0;回油後,指針略高於55.88cm-Hg
5.STICKING VALVES: When the needle (dotted) remains steady at a normal vacuum but occasionally flicks (sharp, fast movement) down and back about 13 kPa (4 in-Hg), one or more valves may be sticking.
氣門積碳 :當指針穩定在正常指數,但是有時候會突然晃動或上下到10.16cm-Hg左右,有可能1或多個氣門積碳.
6.BURNED OR WARPED VALVES: A regular, evenly-spaced, downscale flicking of the needle indicates one or more burned or warped valves. Insufficient valve clearance will also cause this reaction.
7.POOR VALVE SEATING: A small but regular downscale flicking can mean one or more valves are not seating.
8.WORN VALVE GUIDES: When the needle oscillates over about a 13 kPa (4 in-Hg) range at idle speed, the valve guides could be worn. As engine speed increases, the needle will become steady if guides are responsible.
9.WEAK VALVE SPRINGS: When the needle oscillation becomes more violent as engine rpm is increased, weak valve springs are indicated. The reading at idle could be relatively steady.
10.LATE VALVE TIMING: A steady but low reading could be caused by late valve timing.
11.IGNITION TIMING RETARDING: Retarded ignition timing will produce a steady but somewhat low reading.
12.INSUFFICIENT SPARK PLUG GAP: When spark plugs are gapped too close, a regular, small pulsation of the needle can occur.
13.INTAKE LEAK: A low, steady reading can be caused by an intake manifold or throttle body gasket leak.
14.BLOWN HEAD GASKET: A regular drop of fair magnitude can be caused by a blown head gasket or warped cylinder head-to-cylinder block surface.
15.RESTRICTED EXHAUST SYSTEM: When the engine is first started and is idled, the reading may be normal, but as the engine rpm is increased, the back pressure caused by a clogged muffler, kinked tailpipe or other concerns will cause the needle to slowly drop to 0 kPa (0 in-Hg). The needle then may slowly rise. Excessive exhaust clogging will cause the needle to drop to a low point even if the engine is only idling.
When vacuum leaks are indicated, search out and correct the cause. Excess air leaking into the system will upset the fuel mixture and cause concerns such as rough idle, missing on acceleration or burned valves. If the leak exists in an accessory unit such as the power brake booster, the unit will not function correctly. Always fix vacuum leaks.
|
