Hi I have a 94 grand prix and within the last month or so the rpm has gone up and down instantly mostly on acceleration but a few times on idle but it has only died 2 times .It started doing this every few days when it got normal temperature but then it started doing it anytime .I have replaced the plugs,wires,coils,icm and the only thing I have not replaced is the crank pos. sensor and I have had it to 3 local shops including a gm dealer before I replaced all ,and no luck and the worst part there is no codes at all after I replace all listed it stopped for a few weeks but a few days ago it started doing it again ,Has anybody had this problem ?
