My truck has a rough/shaky idle. The RPM stays fairly consistent, but will drop a little and pick right back up. Nothing to bad. I was told I had a sluggish 02 sensor and changed it. I also changed my plugs and wires. One cylinder appeared to have some sort of fouling on it, but noting serious. After I changed all of that it ran very well. 100 miles later its doing it again. I checked the spark plug that was previously fouled and looked fine.

I also was told my ignition pack may have a weak spark, which happens to be the foul plugged cylinder. I've cleaned filter, MAF, idle control valve thing, all of the injectors sound fairly good. NO CODES. Could it be my ignition pack? I've about lost hope.

Also, when it started idling like that again, It seems my truck tries to pulll. It is like it doesn't want to idle down at low speeds making corners and such. Thoughts? When it was running smoother it didn't do that.