camarosource

iTrader: (1)

HOW important is the recirculation tube for the catalytic converters and emission passing??

My car, a 1992 Camaro Z28 with custom chip, mild cam, headers and flow master exhaust (with 2 brand new catalytic converters which are welded with flanges for quick replacements when emission testing occurs... It will NO LONGER PASS AIRCARE (BC Emissions testing).

I left the car with the dealer and they have had it for 3 WEEKS and have no idea why it won't pass. They re-installed the cats, and it failed. They have replaced the EGR valve, O2 sensor, checked gas cap, compression, air/fuel, and no matter what they do, they just CANNOT get it to pass. In fact they have been working with aircare (the mechanic of 20+ years who also owns a custom Camaro has been working with aircare and aircare isn't having any luck getting it to pass). They have given me a CONDITIONAL PASS (3-month) and even so aircare is CLOSING DOWN in December, you still MUST pass aircare within the 3 month period (just means you can renew your car insurance for the time being but if you don't pass within 3 months you cannot renew next time).

Last time they just had to RETARD the timing down so the car ran like CRAP and it passed with FLYING COLORS.. This time THAT is just not enough.

The ONLY thing *I* can think that is different THIS time and LAST TIME (2 years ago which was the last test) was that the car comes with 2 catalytic converters with AIR TUBES on the headers, and recirculation tubes under the car that connect to each catalytic converter. LAST TIME 1 was connected and the other BROKE OFF. So only one was working however with the timing RETARDED it passed.. Immediately after passing, I REMOVE the cats and replace the straight extensions however that leaves the recirculation tube "PIPE" dangling as was vibrating against the frame of the underside of the car. It eventually BROKE off so there are NO TUBES anymore (Both broke off right at the coupling from 1 pipe to 2 pipes (1 to each cat).

I didn't think it was all that important and at the time I was unable to find a replacement anywhere online.

HOWEVER according to Wikipedia, articles online, aircares website, and exhaust websites, emissions WILL FAIL if the "PIPE" is not connected to the cats otherwise the cats don't work to their full potential.

I've found that I can buy the "PIPE" online but what are the chances that is NOT the fix because this pipe will easily be $300+ by the time it arrives, not including install.. Likely $500-600 by the end if not more just to pass aircare (fully) and then never deal with it again..

Recirculation tube "PIPE" which is NUMBER #16

MoJoe

iTrader: (5)

You are talking about air injection into the cats. Is the smog (air) pump on your car still present and hooked up? It is the lower pulley on the passenger side. Is the diverter vale still connected and wired? It is right behind the AC compressor. The fresh air (plenty of O2) feeds the three-way catalytic converter, making the back half work better... The front half does not want extra O2, while the back half does.

I would think having a shop fab up replacement stainless steel 1/2" tubing would not be too expensive. I've purchased air parts/supplies from PCI: tubing here, and fittings here. They HAD 1/2" both ID and OD to make piecing a system together pretty straight forward. I didn't see both with quick browsing.

sofakingdom

iTrader: (1)

Last time I needed one of those, I used a piece of flex gas line, like for water heaters and furnaces, and compression fittings to hook it to the remains of the tubing.

Like $20 at the hardware store.

eseibel67

Not sure how close you are to passing, but on these cars you can immediately reduce the amount of fuel by 12.5% by unplugging one injector. I would suggest #4 since the connector is easy to get at, and since the O2 sensor is only sniffing bank 1, the computer won't even try to add any fuel to compensate.