Has anyone heard of something called a Swedish tune? I spoke with a technician at a Volvo dealership in Michigan about a clogged vacuum system(on my 95 850 turbo) and after he recommended cleaning the elbow he suggested I do a Swedish tune on my car which consists of doing a regualr tune up with timing belt and tranny tune and the take it out on the freeway, get it up to about 45 mph, put it in 1st gear and drive at about 60mph for 12 minutes or 12 miles(in 1st gear). His logic was that these cars are made for high rpms and that this will blow all the carbon off the valves are rings. Sounded a bit scary. I later spoke to another Volvo tech in Alabama and he claimed that Volvo sent a memo to dealerships telling them to perform this operation to start a fire in the catalytic coverter to clean it? So what is the real story? Anyone heard of this Swedish tune?

Im not sure about that I would put a good injection cleaner like techron in the tank and runn it good that will do about the same thing.

I've heard (and tried performing it successfully) of driving the engine for 10-15 minutes in 'L' mode while keeping the RPMs between 4000 to 5000 cycles, before. :)

But that was to get rid of the sticky hydraulic lifters problem.

I am not sure about anything else.

As for the catalytic converters, well, your concerns are not baseless. If the cat is clogged, the effect on the engine would be detrimental, and in some cases, permanent. :huh: So, if you think it is nearing its end, just change the cat into a new one.

Either back into a new cat, or just fix a straight tube in. (Of course, environmentalists are not going to like this option... so if you're going for this cheaper option, don't tell anyone, OK?)

:)