Work visa no work

So I am just about to finish my contract with my current employer. But my visa is still vailed till the end of the year. I know I can change jobs as long as it's within my current visa status. But how long do I have to find a new job? Everywhere I have looked online says once I have a work visa I am good. But I have a friend telling me that I need to find a new sponser for my visa even though I still have plenty of time left on it. If it helps I am from Sweden. My visa type is Engineer/specialist in humanities/int services

You can stay until your status expires or immigration decides to revoke it.

that was true in the past.
they have introduced Zairyu card. it means you are "numbered".
your work (income) is reported by your "my number".
therefore, they will know your work during the stay.
I believe that they will refer to those data, when you apply a renewal.

That makes absolutely no sense.

You can change jobs, you can look for a new job after you've left your current employment (even now of course), and it has been suggested that you are OK if you find a new job within a relatively short time, like a few months (2 - 3 months). But both your employer and you need to report to the authorities that your employment has ended within two weeks of that happening, so the authorities will know anyway.

First of all be smart and don`t take risks.

The standard work visas are actually not tied to a specific employer, but rather to a specific work category. Therefore, generally when one changes jobs with a significant amount of time left on his/her current work visa, it is not necessary to go through a chunky visa procedure at the time of job change. However, according the Japanese immigration law, that due to the introduction of a notification system from July 2012, the majority of work visa holders are now required to submit a notification to Immigration to give notice of changes in company address, roles or changes in employer.

Generally, work visa holders have an obligation to notify the Immigration Office within 14 days of a job changing event (e.g. leaving a job, starting a new job, etc.). The Immigration Office has the right to cancel a work visa in cases where the visa holder is not engaging in the corresponding work for 3 months or longer without legitimate reason.

Generally, you can�ft keep your visa until it expires if you�fre not working, or as Immigration puts it, not �gengaging in authorized activities.�h Ultimately, however, Immigration will make decisions on a case-by-case basis.

I am also an engineer working in Japan since 13 years.
You cannot remain unempoyed on enginner visa for more than 3 months. justmyday is correct.
But if you are searching the new job, immigration may give you another 3 months to search new job.
You are contributing to the country. They will allow you to search new job.
Please refer the below links.
http://www.juridique.jp/visa3.html
http://www.japantimes.co.jp/community/2012/07/31/how-tos/how-would-cha...
Now a day, because of reducing trend of population, immigration is giving 5 years visa to enginners at first time. The new people coming to my company are directly getting 5 years visa. Now the Japan govt will allow engineers to apply PR after 1years after march 2017. Please see this news.
http://asia.nikkei.com/Politics-Economy/Economy/Japan-to-offer-1-year-...

The "you can't stay unemployed more than three months" was nonsense before, and it's even bigger nonsense now that the "grace period" was abolished. The only correct answer on this thread is mine.

Cases where the Minister of Justice may revoke the status of residence are roughly categorized into the following;

The case where a foreign national staying in Japan with the status of residence listed in the Appended Table I of the Immigration Control Act ("Engineer," "Skilled Labor," "Specialist in Humanities/International Services," "Student," and "Dependent," etc.) has failed to continue to engage in the primary activity corresponding to that status for three months or more

In any case, it is always better to talk with immigration about your matter. You can do this by phone or visit your nearest location.

The "you can't stay unemployed more than three months" was nonsense before, and it's even bigger nonsense now that the "grace period" was abolished. The only correct answer on this thread is mine.
I mentioned the links of immigration. One must do the activities of his status. The work visa is given for working and not to remain idle. After somebody lose his job, he/she can remain unemployed for 3 months, then immigration can give you bounus period of 3 to 6month for finding new job. It is case by case.
Even Eiju(PR) is given for working, paying tax and not to remain idle. If some PR holder remain unemployed for more than 1 year, they may remove eiju and and reduce toy 1 year visa. I heard about such case too about eiju holder.