Consider the facts:
Usually, there is only one reason why the oil pressure light comes on briefly and then goes out again: when, after changing, the filter is empty for a moment. But you can confidently leave the stopwatch where it is, because the time taken says nothing at all about filter quality.
The delay can be dangerous if the warning light no longer goes out – because then the oil pressure is too low. Apart from a low oil level or a defective oil pump, the problem may also be caused by the filter:
- the flow resistance is too high because an incorrect or low quality filter has been used
- the filter is full because the change interval has been exceeded
— always on the safe side
With quality products from MANN-FILTER, you can be sure that your filter is not at fault if the oil pressure light comes on. Because they conform to OE specifications and therefore guarantee optimum function at all times. Also, quality filters from MANN-FILTER have an accurately functioning bypass valve,
which is adapted to the engine and always opens and closes at the right time. Bypass valves used in cheap filters, however, are often badly made, or are even permanently open and therefore do not offer any comparable filtration performance. And unfortunately, no warning light will tell you that.
Not a question of time
If you install an oil filter without a filter element, the oil pressure light goes out immediately – because the oil flow then has the least resistance; however, it is of course not filtered either. That says it all. If after being switched on, a smartphone is powered up extremely quickly, you cannot conclude from this that you can make calls particularly well with it.
Brief and to the point: Therefore, the time before the warning light goes out does not lead to any conclusions about the quality of the filter used.