M44 Rough Idle/Misfire After Spark Plug Change
 

Had the valve cover gasket done as when I checked the spark plugs there was some oil. Got it back an it was fine, decided to change the plugs as they may have been bad from leaking oil. Took old plugs out, some had oil on them, looked dirty over. Changed them and now has terrible idle misfire and will barely idle. No idea what happened, changed plugs again. Same symptoms. What now?

Well when running the car, taking the wires off plugs #3 and #4 (two closest to the firewall if i'm correct) the idle did not change and all but did with #1 and #2. Used a multi-meter and tested resistance and #1 and #2 had little resistance while #3 and #4 did not. Got new wires ordered to see if that is the issue and not the coil pack.

old post, but i am having the same problem. Was it the wires that were the problem?

It was. I got new wires from Pelican pretty cheap. Be careful with the wires and use the little blue tool. That is how I broke the stock ones.

I purchased these off ebay (yup ebay) they fit 100% amazing and I got them before my 300mile trip and had no issues or anything. well worth the price and they are amazing as well.

http://www.ebay.com/itm/GEGT7610-448...RVT7t5&vxp=mtr