Sunday, June 5, 2011

Sonata 2006 v6–Changing Spark Plugs

First of all, disclaimer:

I’m not responsible for any damage you may cause to your car or, even worse, to yourself using instructions provided bellow. I’m not a professional mechanic and whatnot, so use these instructions at your own risk. Read entire post first and be sure you understand everything before you start it. If you’re in doubt – seek professional help.

Stuff you’ll need:

  • Please refer to this post for most of the tools required;
  • In addition to that you’ll need 10, 12, 14 mm sockets
  • needle nose pliers

Well, here are couple useful links from that contain some information on how to remove intake manifold and spark plugs. This post is not a replacement and its recommended to use official manual as primary source, but those links below are not compete (some steps are missing, some are irrelevant and can be accomplished in a different way):

OK, let’s start.

  • Pop up the hood and disconnect the battery’s negative terminal. Using the 10mm socket remove engine cover:


  • Remove brackets that hold engine cover, you’ll need 10mm socket and needle nose pliers to detach wires, blue arrows are pointing to the places where those wires are attached. Just squeeze them with pliers and push them through.


  • Loosen spring clamps securing hose coming from airbox to throttle body (red arrows). Use pliers to squeeze the spring clamp on a breather hose, slide it off and disconnect breather hose (yellow arrow). Do not disconnect mass airflow sensor connector (green circle), just unfasten the airbox cover and leave it as is. Those connectors are pain in the *ss.. Remove the intake hose.


  • breather hose disconnected


  • “disconnect” oxygen sensor. Well, its not necessary to disconnect them, just slide them of the W-shaped bracket (surge tank stay), and leave them hanging.



  • Disconnect camshaft position sensor (in fact its not necessary, but it would be easier to move airbox cover, since MAF sensor is connected).


  • Slide off injector connector (left) and ignition coil connector (right) from its bracket and remove bracket (or leave it there).


  • Remove surge tank stay bolt (14 mm) and W-shaped bracket.




  • Yet, another connector (which must be the one for variable intake solenoid, but I’m not quite sure).


  • Disconnect manifold absolute pressure sensor (MAPS).


  • Remove 10mm bolt holding purge control solenoid valve in place (red arrow), disconnect its connector (yellow) and remove spring clamp and hose (blue one). Don’t disconnect another coming from it, disconnecting from surge tank is enough.


  • Time for throttle body. There are 3 10mm and one 12mm bolts holding it in place. Remove the bolts, don’t disconnect any harness or hoses as there are no reasons to do that (unless you want to). Be careful, as this ‘thing” is somewhat fragile…
  • Disconnect the two hoses (se below):
  • .. and there are couple more bolts to remove – 2 10mm and one 12mm at the back of the surge tank.



  • Now, the fun part – removing surge tank. There are 2 10mm bolts with with white rings on them and there another 3 10mm bolts and 2 nuts holding surge tank in place.
  • Once the surge tank is removed, cover intake manifold with some rag or towel immediately.


  • Now you have an access to the rear spark plugs(!).


  • Replacement procedure is straightforward for engines with coils, and I described it in details here, but in nutshell:
    • Disconnect coil wire;
    • Unscrew the bolt that keeps coil in place;
    • Remove coil;
    • Remove old plug;
    • Take a new plug, put anti-seize lube on it and install it;
    • Put a little of dielectric grease in coil, secure it with a bolt;
    • Attach the wire;
    • Repeat for all 6.



  • Once all plug are in place, reinstall everything in reverse order.


That’s pretty much it. Time start to finish: 3 hours (give or take half an hour).