I have a 97 3.5 and it has an occasional miss in it. I have checked all the sensors except the O2's and the knock sensor. Changed the plugs, plug wires, and the coil, still no change. After resetting the computer and running the motor I get code number 11, 12, and 55. 12 and 55 i know about. The code 11 though puzzles me. I have checked the crank sensor on both voltage and ohms. Shows good. The motor will idle fine and rev up fine but if you hold the throttle steady it will start to miss occasionally and show the check engine light. About ready to get rid of it! But have to much in it now!

Thank You

 

Don't get rid of it!!The older LH bodies were plagued with this problem.Belive it or not, it is your fuel pump......Not enough flow.I have worked on several of these with this problem.There is supposed to be a flash update to fix this problem,but I can't ever seem to get a single car to reprogram

 

Well I had the car hooked to an ODB II and it passed. There was not one single fault picked up. But now on the way to get this done it missed like a sun of a gun! Still has plenty of power and will accelerate alright, but has an intermittent miss that will make you think the front end is going to fly off of it. (under heavy power). Going to check and make sure my wire harness is ok and check my fuel pressure.