What is a limp mode?
Limp mode is a “safe mode” that the ECU goes into if it detects any malfunction in any of the sensor. The car is drivable in that mode, so that you can take it to a nearest Subaru dealer or authorized mechanic. Q: I can feel my Impreza hesitating and power is surging if I try to accelerate in a smooth fashion. A: You are experiencing a notorious hesitation problem. It happens due to the ECU retarding the timing. It does it, after hearing some noise with its knock sensor and misinterpreting it as detonation. There has been a TSB issued on this matter. It only applies to 97-98 Impreza with MT, though. The TSB # is 11-53-98. If your car is not covered under this TSB, try looking for a solution and more info on hesitation on this website: http://www.geocities.com/hobiegary/hesitation.htm.
