How to properly repair the ignition timing and valve timing
“Valve timing (phase)” What is meant in the end? According to Jilin University, edited by Chen Shui “car structure” on the definition: “valve timing (phase) is entered, the actual exhaust valve open time.”
In order to improve the engine of the inflatable figure, increase engine power, intake and exhaust valve opening and closing both an early and late after the point of view. When talking about valve drive group, the “car structure” that: “The role of valve transmission group is to make the intake and exhaust valve can be by Valve Timing (phase) provides a time opening and closing, and ensure that there are sufficient opening. “” camshaft valve to make certain kinds of work in accordance with the order and valve timing (phase) the timely opening and closing, and to ensure that there is sufficient lift valve. “” engine work, the deformation will affect the Camshaft Valve Timing (phase). “camshaft on the” cam profile should ensure that open and close valves in line with the duration of valve timing (phase) requirements, and so that a suitable valve lift and the lifting process of law of motion. ” camshaft from the crankshaft through the timing belt or timing chain or timing gear-driven and, therefore, “in assembling the crankshaft and camshaft, the timing mark must be aligned to ensure the correct valve timing (phase) and the firing time. ”
By the above description, we can see, the correct valve timing (phase) is a prerequisite for normal work the engine, once the valve timing (phase) is wrong, will affect the normal operation of the engine. In fact, “timing mark alignment” and “valve timing (phase) right” is between a pair of causation. “Align timing mark” is the cause, “valve timing (phase) right” is the result. Under normal circumstances, the assembly must be timing mark alignment, therefore, is the timing mark alignment valve timing (phase) correct and ignition sequence (ignition timing) a prerequisite for the correct, that is, to valve timing (phase) and the ignition sequence (ignition timing) are correct, you must timing mark alignment. However, it is noteworthy that the timing marks are not aligned valve timing (phase) correct and ignition sequence (ignition timing) a sufficient condition for the correct, that is, even if the timing mark alignment, and with gas being time (phase) and the ignition sequence (ignition timing) is also not necessarily correct. This is because when the transmission is there are many parts, crankshaft drive through the keys or too tight fit means the crankshaft timing gear drive (chain) wheel, and then through the timing belt or timing chain driving the camshaft timing gear (chain) wheel, camshaft timing gear (chain) wheel drive through the keys or the interference fit method driven camshaft, camshaft and through tappet, tappet, rocker-driven or direct drive valve opening and closing, which there are many intermediate links, any of them a part of problems, such as misplaced keys, timing belt aging, timing chain wear, deformed or worn camshaft, hydraulic valve tappet clearance errors or failures Dengjun will ultimately impact “into the exhaust doors actually open moment “, which is affecting the valve timing (phase), leading to failure.
Terms of the modern electric car, the engine ECU still need to use the crankshaft position sensor, camshaft position sensor to detect the location of the crankshaft and camshaft in order to determine the correct injection timing and ignition time, then the crankshaft position sensor, camshaft position sensor signals are not allowed to also lead to the engine ECU to monitor the “valve timing (phase) is not correct. for now with variable valve timing system of the vehicle, such as Guangzhou Honda Accord cars, VTEC, i-VTEC system, Toyota series car used by VVT-i system, VW / Audi cars with variable valve timing (phase) systems, variable valve timing system failure, ultimately affecting the “intake and exhaust valve opening time of the actual”, lead to valve timing (phase) error. in the above-mentioned components and systems failure cases, the timing marks align again, valve timing (phase) is also wrong, the vehicle still fails.
Therefore, we must remember:
1. To valve timing (phase) and the ignition timing correct (result is correct), you must align timing mark (due to correct).
2. In the system normal circumstances, the timing mark alignment (due to the right), valve timing (phase) and the ignition timing must be right (the result is correct).
3. Timing mark alignment (reason correct) and do not represent valve timing (phase) and the ignition timing correct (result is correct). The valve timing (phase) and the ignition timing correct (result is correct), then the timing must be right mark (reason correct).
So we embark on vehicle fault diagnosis, when the suspect vehicle, “valve timing (phase) error” (that is suspected of the results of error), we should not just go to check “whether the timing mark aligned” (check whether the reasons for existence) . Instead, it should first make sure, “Valve Timing is correct” (the result is correct), when the “results” really wrong, we again confirmed that the “reason” is correct (timing mark whether the alignment). That is, when the suspected “cause and effect relationship” if a problem occurs, we should first make sure the “result” is correct, in the “results” really wrong circumstances, again confirmed that “cause” is wrong. The vehicle so as to accurately locate the fault.
However, in practice, the maintenance, repair technicians are often suspected of “Valve Timing” error when the first reflection is to check “is when the number” is aligned, indeed “is not aligned when the mark” (the reasons for the error) will lead to “valve timing (phase) error” (the results of error), but the maintenance staff has ignored the “timing mark alignment” (the right reasons) will still have a “Valve Timing error” (the results of error) of the objective facts, in fact guilty of the “reasons (timing mark alignment)” as a “result (with gas-phase correct),” the “cause and effect upside down” logic error.
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