Car failed emissions (badly), so i'm replacing stuff. Will a stock catalytic converter fit into an aftermarket exhaust kit (stainless steel from block to rear bumper)? Or am i going to have to figure out where this exhaust was purchased (probably e-bay, before i purchased the car)? Thanks

(and just in case you wonder why i need a new cat: when i bought the car the rings and valve seals were shot, blowing all kinds of fumes, and now the inside of the entire exhaust is coated/baked with black soot/carbon, so i doubt the cat is working)

Side note: car failed emissions for NOx and HC... which seems to tell me that some cylinders are running rich... and some are running lean... any ideas?

Edits: would have searched, bump search function seems to have been dead for days for me. Can take pics of exhaust if you gurus could tell me if a stock one would slap in it's place or not... or other ideas.

I've read all the stuff on fuel injectors, and how to tell if they're working or not... blah blah blah... but i haven't figured out a way to test them for leaks??? I know atleast one of them is leaking because it loses fuel pressure after sitting 4+ hours, but have no idea which one to replace, and will be replacing with another used one (from one of my 3 spare engines). Aaaargh. The one thing VW made easier to check... lol


Modified by civic_dork at 1:05 PM 8/20/2005

 

good cats on eBay are 55+/- shipped for the magnaflow kind...I put one on my wifes Accord and it worked great...CEL is gone...and her car is OBD-2...

 

Thanks, checked ebay and found a few high-flow ones, i'll assume there gonna work as well as stock low-flow ones?

*i'm still wondering how crappy a civic (mine) has to run to fail smog*

 

I just failed for NOx (it blew about twice the standard). I have a 92 Civic hatch with USDM 1994 b18c1 swap (USDM GSR). The car passed last year, but it had the factory GSR manifold, a regular cat and factory exhaust. Now, I have a DC 4-1 header, Carsound catalytic converter, and Greddy SP2 exhaust system.

There is definitely a build up of soot around the exhaust, like in the above case.... I suppose I may be running rich as well.

Is there anyway that I could reduce the NOx reading w/o changing the cat? I would say that unless the header could affect the emissions (which doesn't seem probable), then the high-flow cat must be the main issue.

Anyway, please advise me of ways to reduce the NOx level without changing the cat, if possible. I would definitely suggest to be careful when purchasing a high flow cat.....

 

To the guy right above this post, what makes you think you're running rich? People just pull this **** out of their *** I swear. If you were running rich, you would have failed HC. HC = gas.

High NOx are caused by high combustion chamber temperatures. Your ignition timing could be too far advanced. Set it dead center to spec. EGR malfunction may or may not apply to you. You could have carbon build up, so use Seafoam in the gas, oil, and brake vacuum line. Try a higher octane gas. And finally, replace the cat. Cat failure is always a result of some problem so first fix the problem.

Not sure but maybe the wrong spark plugs could have an affect on NOx.