Review on OE Replacement New Exhaust Manifold Catalytic Converter (674-933) for 2007-2012 Nissan Altima 2.5L L4 with Hardware (Replaces OE Part: 14002-JA91E) by Ronnie Dunn

AAA+ quality and price. However, the manifold has two lower heat shields and a third upper heat shield. The bolt locations on the bottom two shields mostly matched, but one hole on the shield did not match and had to be modified to enlarge the hole so I could line it up. My best advice is to attach the two bottom shields to the engine block prior to assembly and tighten the bolts but do not tighten or tighten until all the bolts are in place to allow the heat shield to slide during alignment. When all the screws are in place, tighten them. The upper heat shield must be attached after the header has been attached to the engine block, making it much more difficult to align the bolt holes in the fairing. The bolt hole braces were not welded at factory angles like the OEM header, so it is difficult to install the bolts in the engine compartment. Also, don't re-tighten the bolts, just let them run as you will have to move the heat shield to thread the bolts onto the threads for the bottom holes. They didn't fit together perfectly and I had to use my camera phone to mount the screen and multiple mounts. Swearing for half an hour and finally putting up a shield. Finally. The header bolts on the OEM exhaust manifold that the midpipe connects to have tightened bolt heads. The cap screws that came with this item were bare and had no head to tighten. You have one hand, tighten the bolts and then install the nuts and tighten them with a wrench. These included screws require a head to tighten prior to installing the center section flex pipe. It could have been easier with a better hardware kit and more precise welding of the mounting holes. I hope I don't have to take the heat shield off anytime soon as it's a pain to put back on. I'd also recommend getting new O2 sensors while you're busting everything. In addition, factory oils should burn out on the surface in a few days of driving. This new manifold will smoke as the heat stress burns the surface oils. Don't be alarmed if you see smoke coming out of the distributor, this is normal and will burn out. Leave the car with the hood open for a while and the worst will burn out.