2002 Hyundai Santa Fe, Has sluggish acceleration, low power,( takes 30 seconds to accelerate to 30 mph in ist gear), and can't maintain 60 mph in 4th gear when it finally gets there after reving up in lower gears. computer always shows U0000, and P0501 codes. These were read on a generic scanner, which says P0501 is a speed range/performance sensor, and has no listing for U0000. Anyone know which speed sensor this code refers to, and the location for it?