I have just done a HG on my N*. Everything seems to be OK. The engine was out of balance, but I wouldn't call it missing when I first started driving it. Each time I drive it it seems to get better. The milage is 23.5. I put in new plugs. I looked at the front bank and if anything they are burning a little lean. I will ocassionally stumble at idle and when it is lugging on a hill. The tac will also occasionally jump around but there is no noticeable affect on the engine when the tac is irratic. Before the HG job the coil paks seemed to be making a clattering noise, that is gone now, the only differnce on the ignition side is new AC plugs. I'm sure the next logical move is plug wires and coil paks. Any advice on the how to diagnose this further.
Automobile(s): White Diamond '03 DHS (with DTS floor shift)
Re: Engine miss
Mist the wires in a dark place at night and look for a light show. I'd suspect the wires before coils, especially if they are original and the fuel rail recall has been done. Seems to be a common problem afterwards.
Yes. Asside from the engine misfiring badly the tach was randomly jumping around. I added a 12 ga. wire from the ignition module to the strut tower and the erratic tach completely went away. I can't get the engine to body ground wire off to clean it. The stud is too rusted. I'm soaking it for a while rather than risk breaking it. The clattering sound I refered to in the earlier post was the PCV valve. Just replaced it and the split rubber boot connected to it. I can here noise in the coil area. When the engine is cold or running at highway speed the engine is almost smooth, under load there isn't much power. I just ordered a complete used ignition module with coils. It is supposed to be off a wrecked 95 car. For 50 bucks its worth a shot.
Another trick that I think it was Ranger taught me, is to just trade your existing coil packs around and check for spark loss and it will tell you what coil pack is bad. The one that is bad will be the one that has no spark no mattter where you install it. Another thing, you can see if the contact area is dry of grease between the mounting plates.