What steps are required in removing and replacing both valve cover gaskets on this car. I can not find specific instructions on what items to remove to gain access to the cover.
Valve Cover Gasket Replacement on 2003 Mitsubishi Diamante
Here is a link that should help you get the info you need. http://bit.ly/autozone_repair_info.
Thanks. I have experience working on cars, however I own BMW and Nissan's, this is my GF's car and it is discontinued so its quite hard to find the steps online. That site seems to work perfectly and gives the steps I needed. One last question, Should I use some RTV sealant to help prevent the formation of leaks, or does the gasket itself do a good job of that already? If so, which brand, type to get (sealant)?
I believe the gasket/seal will be rubber so no I do not recommend sealer. Make sure surfaces are clean. Will not hurt to use a thin film of sealer when trying to hold seal in place as lower to the engine so as not to fall off valve cover. Of course there will be many opinions about the sealer but mine is from experience that has worked for me.
Second questions. After looking at autozone repair guide, it talks about the front valve cover removal and replacement. However the gasket comes in two and from my research, there are two valve covers. Is this leak coming from the rear one, since it is coming from the back of the engine by the firewall. Image can be found here of the leak: http://img855.imageshack.us/img855/3296/img1709s.jpg the way the screws are it does look like this could be the other valve cover. The only issue is, if it is, I am not sure how to get to it since the air intake manifolds are over it. Another image of the engine: http://img251.imageshack.us/img251/2433/img1705b.jpg
Not uncommon to have to get air intake plenum gasket and remove that air intake for access. Heck to tune some vehicles with v6 you have to do same thing.