dear people, I have a passat combo with VR6, 174hp, year 1993. Compression is still good, brought so far even in good weather 210km/h peak on tacho. For a long time however electronic problems. now they have told me at VW, because the idle is irregular, that the control chain tensioners are probably worn out. that means a bigger repair, you have to decompose the gearbox to get to the drive. Is it useful to change the control chains immediately, there is wear mass, e.g. stretch ? which expert knows about this ? please answer as pm if necessary. thank you for the help Jochenen