Mitsubishi Repair Problems? Ask a Mechanic for Answers ASAP
There really isn't any valid reason to think cleaning an electronic throttle would have fixed it not revving passed 2500 etc, it is clearly being "turned off" at that point.I would hope they would have scanned the fault codes to see what they were if they erased them.Can you double check that VIN is correct as "JA3AU86U0BU013335" ? It is pretty important as there is a large number of these 2008's that have special warranty provisions that could apply to you.
Perhaps the B is an 8?