         
Some 1996-1998 Jeep Grand Cherokees may experience a bucking condition at wide-open throttle (WOT) acceleration. The symptom will most likely happen at WOT with high electrical loads such as high beams, radio, heated seats, and the HVAC blower motor on max, and when the transmission should be shifting from either first to second or second to third. Supplying the high current needed to keep up with the extra-load demand, the alternator may emit what is called “electrical noise” that can have an effect on the output signal from the transmission governor pressure sensor. Without a clear signal from this sensor, the transmission doesn’t know when to shift. If the transmission doesn’t shift at the right time, the engine will be allowed to rev up high enough to reach the fuel shut off rev-limit of 5,300 rpms. Note: When the rev-limiter sees 5,300 rpms, it begins a program that is designed to protect the engine from damage by systematically limiting the amount of fuel available to the engine cylinders so that it can’t produce enough power to maintain these dangerously high rpms, the end result being a “bucking” Grand Cherokee. According to Jeep, the transmission governor pressure sensor will have to be replaced with a newly designed sensor that won’t be affected by the alternator electrical noise. 1998 Jeep Cherokee Over Charging Examination of the harness found that the field wire can rub through and at times would full field the alternator, check the harness near the fuel rail. Source: Underhood Services & Genco Tech Line 
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