Nissan Repair: Engine noise


Question
Nissan Repair: Engine noise
Metal encasement  
Hey, I'm an expert on the site, also. I'm sorry to bug you, but, I have a Mitsubishi Galant and, to my surprise, there are no experts for Mitsubishi. Anyway, I'm thinking that the issue I am having is sort of general. If you can help, great, if not, not a problem. I have an 04 Mitsubishi Galant. When I start of up, 2 days now, I hear this very loud like bang noise from the engine, 2-4 times, before it turns over. It's loud enough that it turns people's heads. It sounds like maybe a metal part came loose & is banging.

It's coming from underneath some type of metal encasement that I'm not familiar with in any engine I've had. The best I can describe is:It's located in the very front, lower area, a spark plug wire attached into the top left & right side, and coming out of the bottom of this encasement seems to be the emissions (exhaust pipes) I'll try and include a picture to show exactly where it is. Any help that you can provide would be great, thank you.

Answer
Hi Patrick -

The location you indicate is the heat shield of your exhaust manifold. There are no moving parts below it, however, the exhaust manifold may be cracked or loose below the shield, especially if there is a loud sound, like a broken muffler.

I would remove the shield and see whats going on. It should be an easy removal, 10MM bolts, but ensure you spray some oil on it before removing, they tend to break off.

Once removed, see if yo can find something loose, or cracked.

Hope this helps -
aloha

Calvin