Bassani w/ cats failed smog

[hyperider]

My 2004 Cobra has stock headers, Bassani x-pipes with 2 cats and Bassani cat back system. Couple years back it passed smog barely few points. But this time it failed about 24 points on HC(PPM) Max 52 my reading is 76. Some people told me its my x-pipes w/ cats, the cats goes bad after a few years to just put back my stock ford x-pipes. But when I called Bassani technical they said that it's 95% the problem are the 02 sensors that goes bad. So he told me to just replaced all four 02 sensors on the x-pipes and I can get away with not putting back my stock x-pipes. So can somebody give light to this on what should I really do? Shall I go ahead and try just replacing my 02 sensors or I really need to install my stock x-pipes back? Its a pain to do it almost no muffler shop here in California would do it now because they said it's illegal. The old shop I use to go closed down. Plus my tune will be all messed up if I go back to the stock x-pipes unless I don't have a choice.

Thank you in advance! I appreciate any feed back I could get.

 

[ThatOneCobra]

I had Bassani cats and they failed smog. They give out after awhile. I would say just install ur stock midpipe for the smog and then put the bassani back-on , or just pay someone to "PASS" it.

 

[03 DSG Snake]

Reflash your stock tune and do it. My Bassani cats pass even with their headers. It's all in the tune.

 

[Darko]

Samething happened with my Mach and the Bassani catted mid pipe.

+1^^^ just get a fudged smog.

 

[roy_1031]

Samething happened with my Mach and the Bassani catted mid pipe.

+1^^^ just get a fudged smog.

+2^^^ Ya, there are other ways to pass smog.

 

[hyperider]

anybody in the bay area knows someone that does smog? i'm getting desperate because my due date is fast approaching. so either flash my tune? I have my diablo tuner maybe i should just install the tune again. so nobody here had their 02 sensors broke yet?

 

[roy_1031]

Not me sorry, I'm in SoCal. I haven't had any problems with my o2 sensors failing. Just that the previous owner cross threaded one of the sensors into the o/r x pipe and I had to get a new o2 sensor because the threads were jacked up and had to re tap the x pipe. Good luck, hope you get it all sorted out.

 

[suaveflooder]

03DSG is correct. It's your tune. Richen it up a touch and you will be good to go. I've done it a couple times with different cars with the same outcome. All fail the initial time, then you fatten it up a touch to cool down the combustion, and you pass no problem.

I actually got an 84 carbureted mustang to almost pass with no cats. I was about 7 ppm off :bash:

 

[hyperider]

thanks roy i appreciate it! suaveflooder when your talking reflash does that mean just installing my diablo tuner and flashing it to the computer in the car? sorry not so mechanically inclined here. AED did my tune for me. I also have no clue on how to richen the gas up. but the only part it failed was the HC PPM mine was at 76 and the passing is 52 below. the smog guy said the HC PPM is unburn gas that's coming out. it's actually on the rich side.

 

[suaveflooder]

thanks roy i appreciate it! suaveflooder when your talking reflash does that mean just installing my diablo tuner and flashing it to the computer in the car? sorry not so mechanically inclined here. AED did my tune for me. I also have no clue on how to richen the gas up. but the only part it failed was the HC PPM mine was at 76 and the passing is 52 below. the smog guy said the HC PPM is unburn gas that's coming out. it's actually on the rich side.

Weird. That's a new one to me. Usually when a cobra doesn't pass smog, it's because of NOX (hot combustion chamber/lean fuel mixture).

Hydrocarbons are usually an ignition issue. Check/replace your plugs. It sounds like you might have a misfire.

Is it a place that you can retest at? If so, use your diablo tuner to restore the computer to it's factory tune (this will fix it if it is a timing issue) and change out your plugs. That is a good/cheap place to start.

by your numbers it looks like you just have a pulley, so stay out of boost and you should be good to go while on your stock tune. Just make sure you swap it back. :beer:

 

[hyperider]

yeah i think there could be several things. i might also have bad plugs or also the 02 sensors or i need a re-tune. i think for now just to get my smog cert i'll just look for someone that will do it. then i'll start doing the checks to eliminate which is causing it to fail. yes i only upgraded my pulley, put in a tune and upgrade the cai, bassani catted x-pipes and bassani cat back system. thank you again for your feedback!

 

[Evil homer]

I failed to with bassani catted x but i was running e85 wonder if that mess my smog up lol anywho just paid 50 more to wet there peaks lol

 

[OCSnk]

OP, to address the o2 sensors:

It would be a waste of money to change out all four sensors. The function of the rear o2 sensors is to tell the computer that the cats are in place. The front are the important sensors as they tell the computer the fuel and air mixture via measured resistance readings.

o2 sensor have a life of 60 to 80K miles, so if you are near or over the mileage it would be good to change the front two. Unless there is a code telling you one or more of the sensors has a problem or you are in the mileage range, it’s not the front o2 sensors!

As others have mentioned, it’s either the tune, plugs, or a contributing factor would be an oil change! If it's close to your next oil change interval, go ahead and do it before the smog check. The PCV (positive crank ventilation) system of your vehicle is designed to allow your engine to breath fumes located in oil compartments (oil pan, ect.). The fumes are then burned through the combustion process. If the oil in your engine is contaminated due to inadequate oil changes could very well cause a vehicle to fail the inspection.

Contaminated oils are high in Hydrocarbons (HC) and will present a rich mixture to the engine chambers.

All four o2 sensors are the same! The only differences are the front vs rear connectors have a different configuration!

 

[ProchargedSN-95]

FYI california has got tighter om the emissions the last few years, you highflow catted mid pipes will fail unless you have 4 cats. Best thing to do is swap to stock mid pipe for the smog to pass the sniffer.

 

[hyperider]

thanks for the info OCSnk, i did try to put in all those things you said except the oil change. i have about 78k miles on the car right now and my check engine light is not going on. bottom line after talking to several people with the same set up. we figured its really the cats that got bad or it's just not filtering that much emission anymore. but you're right that if anything to only replace the front ones before the cats on each side.

prochargersn95, you are totally correct. that's what's happening here in california they're getting tighter every year on emission laws and test. so yes the best bet is to keep your stock h-pipes with 4 cats and just swap if its easier to do and have it smog and then swap back your after market x-pipes. i would keep my bassani catted x-pipes because some cops here in california will look underneath the car and check if you have cats. so for visual purposes it looks legal but it can't fool the sniffer.

thanks for the feedbacks and info guys!

 

[2sick4v's]

Mine passed back in 2010 with the catted x but this year it failed. I believe the cats go bad because I started smelling gas when I drove the car. Also the smog guy(knows his shit) said it was too rich. Best thing would be get the stock midpipe and pass the smog then throw your bassani catted one back on. Don't go into boost with the stock one and you should be fine.

 

[hyperider]

Mine passed back in 2010 with the catted x but this year it failed. I believe the cats go bad because I started smelling gas when I drove the car. Also the smog guy(knows his shit) said it was too rich. Best thing would be get the stock midpipe and pass the smog then throw your bassani catted one back on. Don't go into boost with the stock one and you should be fine.

the smog guy said the exact same thing to me. mine was also running rich. yes, that's what i'm going to do it just swap the stock h-pipe back, have it smog and put my bassani's back again. it's a pain but i guess that's the price we have to pay for our beloved toys.