Absolutely, the manifold must seal to contain the compression the engine generates when the spark ignites the gasoline.
either miss firing or most likely your exaust manifold. its common for high milage pathfinders to have exaust manifold bolts break. the loose manifold or broken bolt rattles.
I would suspect that there are problems with the hub. Even if it the quick release or nuts are tights, loose bearings will cause the wheel to wobble or feel sloppy.
It has been my experience that most backfiring problems are cause by intake vacuum leaks. You might want to check the torque on the intake manifold retaining bolts or it may be a worn intake manifold gasket. You might also want to inspect the vacuum hoses for cracks or loose connections. You might also check the timing. If the timing is off, it can also cause backfire and starting problems.
Yes, a loose cable actually could cause those problems, as well as others. I was dealing with a large variety of electronics problems in my last car. They included the problem you described. When I finally took it to the shop, the battery post itself was very loose. They tightened it back up, it took about 2 minutes, and all of my car's problems were solved.Check your antenna connections.
yes but why would you leave it loose?
Yes, cause a reduction of power to the engine. It will result in a power-train malfunction error
Cause a no start situation.
A major leak.
A dirty air filter will cause your car to loose horse power. You may loose acceleration and torque.
None, it might cause oil to spill on your engine or inside of your hood, or a dash light might come on.
A loose engine mount would not normally cause the engine to fall out because each car has several motor mounts. A loose mount could cause the motor to be off of balance.
Yes