dohc101

PART2 that he may of knocked but i got scared and tightened the screws back up, they weren't screws they were stuck in there, I couldn't pull out.Now when I start it I hear noise under the throttle body, COULD I OF OVER TIGHTENED THOSE SCREW THINGS?? So far I had the cleaners put in, spark plugs and wires, fuel filter, new lower radiator hose, cabin air filter and air filter and it passed emissions and inspection 600 miles ago. When I asked him about it he said he doesn't know bring it back after holiday. WHAT COULD IT BE???? People I call say I can still drive it as long as CEL doesn't start blinking IS THIS TRUE??

HELP!!!!2000 ford taurus ses dohc vin#s 69700. My CEL came on a few days ago. my codes are p0303 p0174 p0171. Which are misfire cyl 3 and system lean bank 1 and 2. Plus it runs really rough when cold start for about 10 mins then fine. So I went to the mechanic and had him change my plugs with autolite plat. and wires from Napa and he added a can of seagrass meanwhile before i took it into him I added lucus tune up with an stp fuel injector cleaner. When I got into the car and started it the CEL came back on and it felt like my engine started jumping or bouncing while I am driving. Drove it for 3 miles and parked it. Started it the next day popped the hood and i could hear a hissing noise back by the rear spark plugs so I started to take off the trottle body so I could see if a hose/ vacuum was back there/ PART 1