I have following problem with my Jimny 2001 (1.3 l) that I bought 2 weeks ago. I know that previous owner had similar problems.
When I drive over 110 km/h for more than 2-3 minutes the engine starts to stall. I see that the rev counter jumps down to "0" (despite that the engine is turning as it is still on the 4 or 5th gear) and up to the correct rpm. If I slow down, after 10-15 seconds the engine works OK. If I don't slow, after a few more seconds the engine stops for good for something like one minute.
When the engine stalls I see the "check engine" and "immobilizer" light to flash.
I think that (check engine) flashes due to HC emission when the engine turns without ignition.
There are no problems of this type when I accelerate up to max rpm if it doesn't take too long time. Also nothing like that when I go slowly.
I suspect 'overheating" problems with ignition system elements or the computer. I see that at very low temperature the "stalling speed" is higher.
I would appreciate to get some hints from more experienced Jimny owners.