99 tacoma prerunner

So the past few weeks my truck has been acting up with the CEL coming on, loss of power at times and stalling on me a couple times at low speeds. I've asked about this on the forums before. I was out looking under my hood this morning trying to troubleshoot and lone behold a spark plug was loose as ...seems to me like that was the culprit CEL has gone away now and power seems to be back, mind you it was kind of intermittent before, id be driving on the highway and all of a sudden id bog right down and with the gas to the floor it wouldnt want to rev any higher then 2000...think the loose plug could have been the source of my problem?

Now heres the kick to my little problem though. The problem started a day after i brought my truck into canadian tire for a rad flush because I couldnt do it at home (animals). A co-worker also brought his truck into canadian tire for a oil change about a month ago and after his truck started to act up. Then driving down the road away from work a spark plug FELL out of his truck onto the road........fishy? What am I supposed to go tell canadian tire? Best case scenario theyll give me a coupon for a free oil change..... moral of the story, dont go to canadian tire.

 

Which codes did you pull of your puter?

 

CEL came back on and off again so I bucked up and bought a scanner...all the shops around here were no cheaper then $80 for a scan so I figured why not buy one. PO120 is the code, so tps sounds about right. So much for the spark plug idea..