My 88 Pathfinder (V6, 4WD, 116,000 miles) recently went into fail safe mode (won't go above 2750 RPMs). The computer code was 51 - bad injectors, although the car idled fine. I cleaned and replaced the injectors, no more error code, no more failsafe mode. However, now the vehicle idles VERY erratically - fluctuating between 1200-1800 RPMs continually. There are no vacuum leaks, fuel pressure is good, ignition timing is good, choke functions. I even switched out computers with no change. What would cause the idle to go so bad immediately after replacing the injectors? I'm baffled.