2000 Hyundai Sonata couple problems.

I changed my front 3 spark plugs and one broken wire now and I have very bad rough idle and I could hear clicks? Whats going on? Should I put the old ones back on? The new ones were bought from part-source. What are the order of the plugs just want to make sure I didn't put wrong plug in wrong socket on coil. Car is Hyundai sonata 2000 gls. Now check engine light is on too. I just want to get my already bad car to were it was back atleast.

Sorry to bug you guys.

But I fixed the problem I put two wires on wrong socket. I manged to change my three front spark plug myself. I decided to do that because I saw two of the wires were broken. Now the engine is fine but with engine light on.

Furthermore, I just need to unhook battery to clear the code that was created by coil misfire code. I don't have the tool. What kind of alternative tool can I use to unhook battery?

I also changed my maf sensor with another cars also. For only 30 bucks. That was good news. Hoping anything would fix NOX problem. Don't know if I have the capability to change the 3 spark plugs from the back. Is it easy job as front ones?

The emission place that I did my emission place told me my oxygen sensor were bad cost me 50 bucks to diagnose it

afterward, I took the car to the mechanic who changed one pre-cat oxygen sensor and charged me 130 bucks telling me oxygen sensors are fine and nothing is wrong with the one they changed I was so pissed he even mentioned me paying him he is just checking to see what he has done why charge me. I will never go to those money hungry crooks.

Apparently my precats are suppose to be correcting itself and my precats were jumping up and down on graph correctly ( completely opposite from the emission center told me (which was the graph of the oxygen sensor should be be flat ) I verified from three to four other mechanic places that is absolutely wrong what emission place told me (another private crook) So you can see I am not in good mood.. I am baffled and do not trust most private mechanics anymore.

Also, my oil change is overdue does that matter before I do emission test again this Saturday?

Thanks.

When you do v6 Hyundai sonata 2000 tune up. DO you need a new intake plenum gasket or manifold gasket or they are the same?