Running on 3 cylinders

Well I found out something, I replaced my spark plugs a couple days ago and started to take a drive this morning only to go about 50' and then it stopped dead! Had the Red Triangle and some other faults so I was going to tow it back to my driveway and got to thinking (did I replace all of the connectors) the one on the far right is kind of below some other wiring and a little hard to see so got a flashlight and took a look and sure enough I had failed to re-insert the connector on the plug! Took of the relay box so I could get to it and plug it in and then it started right up and ran fine, so don't forget to put all of the plugs back in place.