Home
Don't have an account? Create one now! It's always free!


Forgot Password
Ed's Auto Parts - Mention MOTORGEN for a Discount!
Motorgen Sponsor: McLeod Racing
Motorgen Sponsor: American Muscle - Add style and performance to your Stang
Motorgen Sponsor: Hall Fabrication & Racing
Motorgen Sponsor: Injectors Plus - Performance Fuel Delivery Systems
Reply
 
Thread Tools
Old 09-04-2013, 12:38 AM   #1
VettezukiVettezuki is offline
I, Vettezuki
 
Vettezuki's Avatar
 
Join Date: Feb 2006
Posts: 14,754
Default Bad O2/Cat Relationship

I have a situation on the Aveo from hell, where I know the O2 sensors are bad because the computer will throw a code immediately after clearing it. Here's the question:

If know the O2 sensors are bad, but don'tkow if the cat is bad, what's the best way to proceed? My understanding is that a bad cat can wreck at least the downstream O2 sensor, and if the ECU gets bad data, it can also lead to a condition where both O2 sensors get toasted.

All I know to do is put in the new O2 sensors, but I'm not going to be happy if they get chewed up right away. How can I avoid that?
__________________
Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(active)
Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(back burner)
  Reply With Quote
Old 09-04-2013, 08:49 AM   #2
DamianDamian is offline
Senior Member
 
Damian's Avatar
 
Join Date: Jun 2009
Posts: 2,509
Default

Before you change the O2 sensors out, you can run the engine for awhile and then use a temp gun to see what the temps are right before and after the cat. If its hotter before the cat, it's bad.
__________________
93 GMC Typhoon: new money pit/PITA. Now GT3788R powered.

Boost, because sometimes atmospheric pressure just isn't enough.

"If it has tit's or tires, you can be pretty sure your going to have problems with them..."
  Reply With Quote
Old 09-04-2013, 09:01 AM   #3
BADDASSC6BADDASSC6 is offline
Internet Tough Guy
 
BADDASSC6's Avatar
 
Join Date: Jun 2008
Posts: 1,545
Default

Check the part numbers on the O2 sensors. If they are the same than a bad cat will not damage the downstream O2 sensor. O2 sensors are $50 to 100 I would just replace it and see what happens.
__________________
2007 C6 z51 416ci, KW variant III, Wilwood WS6, Traqmate.
2005 F-350 PSD 4x4 DRW Lariat
2013 Mustang GT Grabber Blue, track pack, Brembo, Recaro, 3.73s
2009 Jetta Auto 2.5 liter
  Reply With Quote
Old 09-04-2013, 09:23 AM   #4
VettezukiVettezuki is offline
I, Vettezuki
 
Vettezuki's Avatar
 
Join Date: Feb 2006
Posts: 14,754
Default

Quote:
Originally Posted by BADDASSC6 View Post
Check the part numbers on the O2 sensors. If they are the same than a bad cat will not damage the downstream O2 sensor. O2 sensors are $50 to 100 I would just replace it and see what happens.
They're different and quite a bit different in price. Don't know if that's just the length of the pigtail, or something else, but they ain't the same part.
__________________
Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(active)
Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(back burner)
  Reply With Quote
Old 09-04-2013, 10:05 AM   #5
94cobra69ss39694cobra69ss396 is offline
Fast & Filthy
 
94cobra69ss396's Avatar
 
Join Date: Jun 2008
Posts: 3,840
Default

Like Damian said, check the cats with a temp gun. Run the engine at around 3000 rpms for a couple minutes and then check the temp before and after the cat. The temp out of the cat should be about 300 degrees hotter if the cat is working properly.
  Reply With Quote
Old 09-04-2013, 02:37 PM   #6
VettezukiVettezuki is offline
I, Vettezuki
 
Vettezuki's Avatar
 
Join Date: Feb 2006
Posts: 14,754
Default

Thanks for the cat check protocol. I shudder at having to replace that as the cheapest cats are fuck all expensive.
__________________
Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(active)
Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(back burner)
  Reply With Quote
Old 09-04-2013, 02:44 PM   #7
94cobra69ss39694cobra69ss396 is offline
Fast & Filthy
 
94cobra69ss396's Avatar
 
Join Date: Jun 2008
Posts: 3,840
Default

That's where I'm at on the Cobra. I think I'm going to add front cats to the current H pipe which are about $130 each. A complete four cat H pipe is about $550. I might be able to get a stock one that's missing a front cat but I don't know yet. I haven't tested my cats yet but my current H pipe only has 2 cats.
  Reply With Quote
Old 09-04-2013, 02:59 PM   #8
VettezukiVettezuki is offline
I, Vettezuki
 
Vettezuki's Avatar
 
Join Date: Feb 2006
Posts: 14,754
Default

The one (1) cat on the Protege was like $750. I think they are like $650 on the LS1 AIR. It's not total BS though, OEM cats have a lot more catalyst and platinum in them than aftermarket, which borderline isn't even legal anymore. The law is pretty fuzzy to me. Paul would know, but in the Aveo case, basically a dealer item.
__________________
Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(active)
Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(back burner)
  Reply With Quote
Old 09-04-2013, 03:27 PM   #9
Shaolin CraneShaolin Crane is offline
pain's fun, hit me again
 
Shaolin Crane's Avatar
 
Join Date: Sep 2009
Posts: 6,264
Default

Quote:
Originally Posted by 94cobra69ss396 View Post
That's where I'm at on the Cobra. I think I'm going to add front cats to the current H pipe which are about $130 each. A complete four cat H pipe is about $550. I might be able to get a stock one that's missing a front cat but I don't know yet. I haven't tested my cats yet but my current H pipe only has 2 cats.
I never used the cats you gave me. You're welcome to them back.
__________________
Quote:
Originally Posted by Bruce Lee
Forget about winning and losing; forget about pride and pain. Let your opponent graze your skin and you smash into his flesh; let him smash into your flesh and you fracture his bones; let him fracture your bones and you take his life. Do not be concerned with escaping safely — lay your life before him

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Stopping the world!
  Reply With Quote
Old 09-04-2013, 04:13 PM   #10
LeedomLeedom is offline
Graphics B*tch
 
Leedom's Avatar
 
Join Date: Dec 2006
Posts: 2,197
Default

Give me the part numbers for the O2 sensors and I will check to see if we manufacture them. If we do I might be able to get you a good price on them.
__________________
Adam

'13 Ford Fusion SE (2.0L EcoBoost)(Conor)

'03 Zinc Yellow Mach 1(Yazmine)
290HP / 305TQ
1/4 mile ET: 13.28 @ 101MPH (1.867 60')

'99 White F-150 (4.6L)(Bud Jr.)-gone but never forgotten
  Reply With Quote
Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off


All times are GMT -7. The time now is 02:02 AM.