New Cats Smell! Open Loop Problem... - TCCoA Forums
 
LinkBack Thread Tools
post #1 of 11 (permalink) Old 03-11-2008, 11:39 PM Thread Starter
PostWhore
 
MadGoat's Avatar
 
Join Date: Apr 2004
Location: Tucson, AZ
Age: 34
Posts: 1,072
Send a message via AIM to MadGoat Send a message via MSN to MadGoat
New Cats Smell! Open Loop Problem...

Ok, got new exhaust. New Cats too. And I noticed they sometimes smell. (gets pretty rank in the car, but goes away fairly quick) So I figured I might be dumping too much fuel, and maybe O2 sensors might be to blame. (I've never replaced them, so I figured I might as well) So new O2 sensors, reset the computer and took here for a nice long 1.5 hour drive, keeping as constant pedal and speed as possible. Seems the smell is quite a bit better now, but still noticeable at times.

So with all this information I set my scan gauge to show TPS reading, rpm, and closed/open loop.

Here is what I found,

First of all it shows TPS at 19 at idle... Why? And anything above 32 the computer goes into Open loop! WHY? thats like 1/4 pedal!

And second, I found a correlation between when the computer goes into open loop and the cats smelling. When I take off from a light, if I do anything over the 32 TPS mark (where the computer will then go into open loop for a couple seconds, then closed when I start coming out of the throttle while im coming up to speed) I will smell the cats.

Further more, the cats are starting to turn colors! Their brown now, but I fear if I keep driving it they will soon turn blue indicating WAY too much heat. (also magna wont warranty them if they show these signs of heat)

PLEASE HELP!

~MG~

MadGoat's Birds
94 Thunderbird LX 4.6L PI
03 Aluminum PI Engine, J-Mod, Aluminum one piece drive shaft, 3.27's, 2.5" to single 3" custom MagnaFlow exhaust, 07 17x8 Bullit Wheels
97 Thunderbird LX 4.6L V8
RIP
MadGoat is offline  
Sponsored Links
Advertisement
 
post #2 of 11 (permalink) Old 03-12-2008, 12:38 AM
5th Gear Poster
 
strung's Avatar
 
Join Date: Dec 2007
Location: so. oregon
Age: 43
Posts: 377
damn.....if your cats are getting that hot then you are likely running lean for some reason.

pimp'n aint easy

mods: air silencer delete w/ k&n panel filter, magnaflow di/do tru duals w/all cats removed, sct 92 oct tune by blue oval chips, tokico advanced handling suspension kit
strung is offline  
post #3 of 11 (permalink) Old 03-12-2008, 01:07 AM Thread Starter
PostWhore
 
MadGoat's Avatar
 
Join Date: Apr 2004
Location: Tucson, AZ
Age: 34
Posts: 1,072
Send a message via AIM to MadGoat Send a message via MSN to MadGoat
the opposite I would think...

MadGoat's Birds
94 Thunderbird LX 4.6L PI
03 Aluminum PI Engine, J-Mod, Aluminum one piece drive shaft, 3.27's, 2.5" to single 3" custom MagnaFlow exhaust, 07 17x8 Bullit Wheels
97 Thunderbird LX 4.6L V8
RIP
MadGoat is offline  
Sponsored Links
Advertisement
 
post #4 of 11 (permalink) Old 03-12-2008, 10:02 AM
5th Gear Poster
 
strung's Avatar
 
Join Date: Dec 2007
Location: so. oregon
Age: 43
Posts: 377
nope, sounds like a lean mixture to me....a rich mixure will actually help cool the engine....at the expense of bad mileage.....you notice any white smoke out of your exhaust...thats a sign of a lean mixture....we all want the perfet air/fuel mixture....but its always better to run rich than lean....your car isnt getting enough air or fuel for the proper mixture in the combustion chamber....hense, improper burn and more heat....one of my focus buddies had a lean condition so bad that his header would almost glow red hot.....you could simple have a vacuume leak.....but yeah, the first thing to go are going to be your cats if you are indeed running lean.

pimp'n aint easy

mods: air silencer delete w/ k&n panel filter, magnaflow di/do tru duals w/all cats removed, sct 92 oct tune by blue oval chips, tokico advanced handling suspension kit
strung is offline  
post #5 of 11 (permalink) Old 03-12-2008, 10:43 AM Thread Starter
PostWhore
 
MadGoat's Avatar
 
Join Date: Apr 2004
Location: Tucson, AZ
Age: 34
Posts: 1,072
Send a message via AIM to MadGoat Send a message via MSN to MadGoat
interesting because my gas mileage BLOWS right now....


I really want to know why the computer goes OPEN loop at 1/4 pedal though... I would think it should go Open at say 85 or so...

Anyone have an Idea?!

~MG~

MadGoat's Birds
94 Thunderbird LX 4.6L PI
03 Aluminum PI Engine, J-Mod, Aluminum one piece drive shaft, 3.27's, 2.5" to single 3" custom MagnaFlow exhaust, 07 17x8 Bullit Wheels
97 Thunderbird LX 4.6L V8
RIP
MadGoat is offline  
post #6 of 11 (permalink) Old 03-12-2008, 11:35 AM Thread Starter
PostWhore
 
MadGoat's Avatar
 
Join Date: Apr 2004
Location: Tucson, AZ
Age: 34
Posts: 1,072
Send a message via AIM to MadGoat Send a message via MSN to MadGoat
Just did some research and found that my thoughts were correct. Rich conditions (over fueling) will overheat a cat, to the point of damage. The excess fuel reaches the cat, and by means of chemical reaction (that the converter is originally designed for) heats up as a byproduct of the reaction.

Although a lean condition will cause high exhaust temp, the cat itself is not to blame. I do believe my situation is a rich condition, also because I have no symptoms of a lean condition. (No pinging etc...)

A thought actually just popped into my head... Think It could be a faulty Fuel pressure regulator?


~MG~

MadGoat's Birds
94 Thunderbird LX 4.6L PI
03 Aluminum PI Engine, J-Mod, Aluminum one piece drive shaft, 3.27's, 2.5" to single 3" custom MagnaFlow exhaust, 07 17x8 Bullit Wheels
97 Thunderbird LX 4.6L V8
RIP
MadGoat is offline  
post #7 of 11 (permalink) Old 03-12-2008, 12:01 PM
2nd Gear Poster
 
Rockhound's Avatar
 
Join Date: Feb 2008
Location: Winchester TN
Age: 47
Posts: 62
You removed your 3rd cat when you did your exhaust, correct?
Did you do anything with the rear o2 sensors or just unplug them???
Rockhound is offline  
post #8 of 11 (permalink) Old 03-12-2008, 01:18 PM
5th Gear Poster
 
strung's Avatar
 
Join Date: Dec 2007
Location: so. oregon
Age: 43
Posts: 377
huh?....i always knew running rich would eventually kill your cats, but i thought that just congested them...not fried em.....interesting.

pimp'n aint easy

mods: air silencer delete w/ k&n panel filter, magnaflow di/do tru duals w/all cats removed, sct 92 oct tune by blue oval chips, tokico advanced handling suspension kit
strung is offline  
post #9 of 11 (permalink) Old 03-12-2008, 03:24 PM Thread Starter
PostWhore
 
MadGoat's Avatar
 
Join Date: Apr 2004
Location: Tucson, AZ
Age: 34
Posts: 1,072
Send a message via AIM to MadGoat Send a message via MSN to MadGoat
Quote:
Originally Posted by Rockhound View Post
You removed your 3rd cat when you did your exhaust, correct?
Did you do anything with the rear o2 sensors or just unplug them???

Rear O2 sensors are disabled in the tune.

~MG~

MadGoat's Birds
94 Thunderbird LX 4.6L PI
03 Aluminum PI Engine, J-Mod, Aluminum one piece drive shaft, 3.27's, 2.5" to single 3" custom MagnaFlow exhaust, 07 17x8 Bullit Wheels
97 Thunderbird LX 4.6L V8
RIP
MadGoat is offline  
post #10 of 11 (permalink) Old 03-13-2008, 07:46 AM
Seasoned Veteran Poster
 
1995 cougar xr7's Avatar
 
Join Date: Dec 2007
Location: Naples, FL.
Age: 45
Posts: 889
new cats and new pipes smell until you burn off the aluminized coating
1995 cougar xr7 is offline  
post #11 of 11 (permalink) Old 03-14-2008, 10:55 AM Thread Starter
PostWhore
 
MadGoat's Avatar
 
Join Date: Apr 2004
Location: Tucson, AZ
Age: 34
Posts: 1,072
Send a message via AIM to MadGoat Send a message via MSN to MadGoat
I know the new install will take a little while to burn off, but the cats are showing signs of overheating.The smell is also much more powerful than just a new install smell.

MadGoat's Birds
94 Thunderbird LX 4.6L PI
03 Aluminum PI Engine, J-Mod, Aluminum one piece drive shaft, 3.27's, 2.5" to single 3" custom MagnaFlow exhaust, 07 17x8 Bullit Wheels
97 Thunderbird LX 4.6L V8
RIP
MadGoat is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the TCCoA Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



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

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome