What causes catalytic converter damage? - ZR-1 Net Registry Forums

npritchard777 · 09-30-2009

I installed my Corsa system over the weekend and discovered that both my cats are bad. The passenger side cat actually had broken down and a big chunk fell out when the exhaust was cut off it. The driver side is nearly black but hadn't blown apart like the passenger. So I'm wondering what would be the most likely cause this much wear? The car has about 72k miles on it.

I've got a set of FIC injectors sitting in the garage waiting for me to get enough motivation to pull the plenum again. Could the stock injectors cause damage to the cats with bad flow rates?

-Nate

gbrtng · 09-30-2009

Running too rich OR too lean hurts them. And excessive oil usage kills their efficiency over time.

GOLDCYLON · 09-30-2009

As stated above but also impact due to speed bumps, potholes etc damage the honeycomb substrate until it starts breaking apart. Also 72K is about right. THe black may have been previous damage before the injectors were replaced.

If you need a factory replacement passenger side I have one low mileage one about 18K miles on it I picked up in the actic (complete) As you well know the cats and exhaust header are intergrated on the 90-91s.

npritchard777 · 09-30-2009

I actually haven't replaced the injectors yet. I've been dreading pulling the plenum (again) but I'll probably get to that this winter. I'll get back to you on the cat. The guy that did my Corsa was supposed to get back to me yesterday to let me know if/when replacement cats would be in.

With these integrated exhaust/cat, can the cat still be replaced without messing with the exhaust manifold?

-Nate

GOLDCYLON · 09-30-2009

No the 90-91 cats are one unit. So to deal with the cats your going to have to pull the exhaust manifolds on both sides. These are NLA from GM. GM made them seperate units in 92 and the rest of the model run. If he can find a factory replacement I would be very surprised

npritchard777 · 09-30-2009

Well that sucks. Maybe I should just hold off for a while and save some pennies for headers.

-Nate

npritchard777 · 09-30-2009

Oh, it wasn't factory replacement he was talking about. I think he said he found them from Magnaflow.

-Nate

GOLDCYLON · 09-30-2009

Yep I kinda figurered that as im running MFs on my car now but good luck getting it to pass emissions. Mine doesnt and CA is even more anal than AZ. Im running Jeal Long Tubes, With MF High FLow Cats and a Corsa system. With the original Cats I passed no problem.

Dynomite · 09-30-2009

Quote:

Originally Posted by GOLDCYLON

Yep I kinda figurered that as im running MFs on my car now but good luck getting it to pass emissions. Mine doesnt and CA is even more anal than AZ. Im running Jeal Long Tubes, With MF High FLow Cats and a Corsa system. With the original Cats I passed no problem.

I Prolly will install SW headers and exhaust

AND will be registering ZR1 in South Dakota

There are NO vehicle emissions checks in good ole SD for licensing. I think I will run SW offroad headers without CATS

GOLDCYLON · 09-30-2009

Quote:

Originally Posted by Dynomite

I Prolly will install SW headers and exhaust

AND will be registering ZR1 in South Dakota

There are NO vehicle emissions checks in good ole SD for licensing.

Which is why my Z is registered in Flagstaff

09-30-2009	#1
npritchard777 Join Date: Dec 2008 Location: Santa Maria, CA Posts: 33	What causes catalytic converter damage? I installed my Corsa system over the weekend and discovered that both my cats are bad. The passenger side cat actually had broken down and a big chunk fell out when the exhaust was cut off it. The driver side is nearly black but hadn't blown apart like the passenger. So I'm wondering what would be the most likely cause this much wear? The car has about 72k miles on it. I've got a set of FIC injectors sitting in the garage waiting for me to get enough motivation to pull the plenum again. Could the stock injectors cause damage to the cats with bad flow rates? -Nate

09-30-2009	#2
gbrtng Join Date: Feb 2006 Location: San Antonio area Posts: 1,179	Re: What causes catalytic converter damage? Running too rich OR too lean hurts them. And excessive oil usage kills their efficiency over time. __________________ “Buy the best example of what you want, and pay whatever it takes. That way, you cry only once.” ~ Bruce Meyer

09-30-2009	#3
GOLDCYLON Join Date: May 2007 Location: Peoria, AZ Posts: 9,155	Re: What causes catalytic converter damage? As stated above but also impact due to speed bumps, potholes etc damage the honeycomb substrate until it starts breaking apart. Also 72K is about right. THe black may have been previous damage before the injectors were replaced. If you need a factory replacement passenger side I have one low mileage one about 18K miles on it I picked up in the actic (complete) As you well know the cats and exhaust header are intergrated on the 90-91s. __________________ GOLDCYLON - 91 ZR-1 #2014 GOLDCYLON - 90 ZR-1 #2794, 4L60e (Formerly Schrade's) GOLDCYLON - 11 CTS-V Arizona State Director 91 WHITE/BLACK #2014. 380 P&P&PCed,Ported Heads, Jeal Long tubes, Corsa Exhaust/FIKSE FM-5s /LED TLs, LED Headlights, Front Wilwood 6 piston narrowlite calipers and rear Wilwood caliper street shop mod,CNCed Coolant Pipes,TPI Cvr,Filter cover,Stainless Bolts, DRM/DOM PROM /ZFDOC mod build #102,DRLs,BMAD with stainless Debris Screen,Coplan Air Blaster, Pioneer APP Radio 4,Brey-Krause HB,Sub Bar,Fire extinguisher seat mount,DRM Coilovers,LEDs everywhere,Compass mirror (orange),V1 DIC hidden display, Homelink sun visor, Carbon Fiber top x3 and APSIS Carbon Fiber interior, APSIS CF Steering Wheel/NAPA Leather, Banski trailing arms, Guldstrand front suspension,urethane bushings from Prothane (total suspension) ZFDoc drive shaft safety loop, raptor shift light (orange),AO engineering louver front plate, Console seat cushion, 96CE seats with black custom Sheepskins, ss billet catch can,Viper remote entry/alarm,Cragar Rear Louvers,LED side louver lights, Dewitts Radiator with SPAL fans and a Woods 160 T-Stat 90 RED/BLACK #2794. 4L60e Automatic Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless Headers, Corsa Exhaust, SAN Secondaries and Haibeck PROM, Exotic Muscle Coil overs, LED Interior Lights, LED Tail Lights, LED Headlights, 94 Sport seats with black custom Sheepskins , Cragar rear louvers, GS Front calipers, Banski Trailing arms, APSIS Carbon Fiber steering wheel, Front and Rear Baer Eradispeeds, DRLs, Guldstrand front suspension,urethane bushings from Prothane (total suspension), Dewitt's Raditor with Dual SPAL fans and a Haibeck 170 T-Stat 11 RED/GREY CTS-V Last edited by GOLDCYLON; 09-30-2009 at 02:47 PM.

09-30-2009	#4
npritchard777 Join Date: Dec 2008 Location: Santa Maria, CA Posts: 33	Re: What causes catalytic converter damage? I actually haven't replaced the injectors yet. I've been dreading pulling the plenum (again) but I'll probably get to that this winter. I'll get back to you on the cat. The guy that did my Corsa was supposed to get back to me yesterday to let me know if/when replacement cats would be in. With these integrated exhaust/cat, can the cat still be replaced without messing with the exhaust manifold? -Nate

09-30-2009	#5
GOLDCYLON Join Date: May 2007 Location: Peoria, AZ Posts: 9,155	Re: What causes catalytic converter damage? No the 90-91 cats are one unit. So to deal with the cats your going to have to pull the exhaust manifolds on both sides. These are NLA from GM. GM made them seperate units in 92 and the rest of the model run. If he can find a factory replacement I would be very surprised __________________ GOLDCYLON - 91 ZR-1 #2014 GOLDCYLON - 90 ZR-1 #2794, 4L60e (Formerly Schrade's) GOLDCYLON - 11 CTS-V Arizona State Director 91 WHITE/BLACK #2014. 380 P&P&PCed,Ported Heads, Jeal Long tubes, Corsa Exhaust/FIKSE FM-5s /LED TLs, LED Headlights, Front Wilwood 6 piston narrowlite calipers and rear Wilwood caliper street shop mod,CNCed Coolant Pipes,TPI Cvr,Filter cover,Stainless Bolts, DRM/DOM PROM /ZFDOC mod build #102,DRLs,BMAD with stainless Debris Screen,Coplan Air Blaster, Pioneer APP Radio 4,Brey-Krause HB,Sub Bar,Fire extinguisher seat mount,DRM Coilovers,LEDs everywhere,Compass mirror (orange),V1 DIC hidden display, Homelink sun visor, Carbon Fiber top x3 and APSIS Carbon Fiber interior, APSIS CF Steering Wheel/NAPA Leather, Banski trailing arms, Guldstrand front suspension,urethane bushings from Prothane (total suspension) ZFDoc drive shaft safety loop, raptor shift light (orange),AO engineering louver front plate, Console seat cushion, 96CE seats with black custom Sheepskins, ss billet catch can,Viper remote entry/alarm,Cragar Rear Louvers,LED side louver lights, Dewitts Radiator with SPAL fans and a Woods 160 T-Stat 90 RED/BLACK #2794. 4L60e Automatic Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless Headers, Corsa Exhaust, SAN Secondaries and Haibeck PROM, Exotic Muscle Coil overs, LED Interior Lights, LED Tail Lights, LED Headlights, 94 Sport seats with black custom Sheepskins , Cragar rear louvers, GS Front calipers, Banski Trailing arms, APSIS Carbon Fiber steering wheel, Front and Rear Baer Eradispeeds, DRLs, Guldstrand front suspension,urethane bushings from Prothane (total suspension), Dewitt's Raditor with Dual SPAL fans and a Haibeck 170 T-Stat 11 RED/GREY CTS-V Last edited by GOLDCYLON; 09-30-2009 at 03:51 PM.