My '94 started having a stumble off idle. It idled fine and ran smooth at higher RPMs. But at low RPMs and off idle it stumbled. My first inclination was to check the spark plugs since I had never replaced them after I bought the vehicle over a year ago and did not know the repair history. It also seems logical since the stumble only happened under load at low RPMs when it was hardest to make a spark. When I pulled the first plug out the problem was apparant. The spark plug body was in good shape, and the color on the electrodes was good but the center electrode was worn way down and was rounded to such an extent that the gap was almost double what it should be. all the other plugs were similar. I put in new spark plugs and the stumble is gone. While doing the plugs I went through the rest of the ignition system. The plug wires tested OK with the longest wire at about 27K ohms when the spec. max. is 25K ohms. Do I replace the wires as a set or can I replace just the one that is out of spec? I tested the coil and it is in spec. on the high voltage side but a little out of spec. on the low voltage side. Might get a new one of those. My main question is on the distributor cap and rotor. The FSM does not give a spec. or time frame to replace them. The contacts on the cap look a little eaten away from the arc and so does the rotor contact, but I do not have a new one to compare it to. What is the recommendation of the list?
Thanks, David Sword
Thanks, David Sword