So I've been reading up on the pre-cat failures and the resulting engine failures on the nissanclub.com Altima web site and I think I am now also starting to see comparable reports of the problem here on Maxima.Org (damaged catalytic converter particles being sucked into the engine through the exhaust and causing dramatic wear to the cylinder walls resulting in excessive oil consumption).

I am now thinking that there could be value in replacing those pre-cats BEFORE the problem happens. My car has over 80k on it so I would have to do this work on my own.

Does anyone know if there are high performance aftermarket exhaust parts available that we could use for this purpose?

Thanks!

Andrew

EDIT: Just found this link from Nissan showing what's been happening to their catalytic converters! (This is for MY04-05 but it shows the damage to the cat quite clearly).

http://www.nissanhelp.com/ownership/.../NTB05-037.htm

 

If it's just the rear precat that causes problems (yeah, i dont know where the EGR valve is), I'd suggest you just buy a y-pipe. You will get rid of the rear precat so I guess you wont have to worry about it any more.

Just a thought...

 

Well, the 2003/2004 years don't have any EGR valve. The point is that folks are talking about having to have engines replaced due to failed pre-cats. The engine literally "sucks" the broken bits of the converter back into the head through the exhaust valves. The photos in the link show what actually happens to the catalytic converter. On our cars all the metal particles dumped from the EGR valve would have just been dumped straight into the head and destroyed the engine. This has already been happening quite widely on the 2.5 Altima and also some 3.5's of all types . . .