Hey fellas, on my newly acquired Pathfinder 3.0 V6 I have discovered a quite troubling exhaust leak. Correct me if I'm wrong but what I can tell, there are 6 studs in the side of the block that the exhaust manifold is placed on the secured with nuts on each stud. Well on the passenger side on the cylinder closest to the firewall my top and bottom studs are both broken off inside the block, which causes the manifold not to set direcly against the block. So I the exhaust leaks from that cylinder prefusely. The only way I could think of to fix the problem is to pull the engine, drill out the studs, tap the holes and place new studs in the block. However, I have less than $500 in the whole vehicle and don't want to pay a ton of money to have the leak fixed when it would cost more than what I paid for the thing. I also then thought well what if the lack of back pressure is causing wear on the rings, could this cause fatal problems quickly?

Broken studs on the VG30E engine are a common problem, especially on the right bank. The engine does NOT have to be removed. The exhaust manifold nuts can be accessed from the passenger side wheel well. Unbolting the 3 flange bolts from the front pipe, removing the nuts and washers will allow you to remove the exhaust manifold from the top (you may need to use a prybar to apply force to the inside of the front pipe to pull the pipe/manifold slightly away from the studs). Once the manifold is out of the way, an angle drill with cobalt bits and stud removers can be used to "carefully" drill out and remove the broken 8mm studs. Nissan has made available "harder" studs that don't break as easy as the original studs. You'll also need to replace any missing washers and nuts and should inspect the manifold for cracks and warpage. Leaking exhaust nor reduced backpressure will damage the piston rings at all. It could cause a burnt exhaust valve, but I can't say I've ever seen it happen on a VG30E due to broken exhaust studs.

I've seen current 8mm exhaust studs going for around $13 for a set of 3 on EBay. So, the good news is these replacement pieces won't carve into too much of your budget.