2003 Corolla...catalytic converter
Kimberly Fox

Tulsa, OK

#62 Apr 2, 2010
same with me, corolla '03, engine light, catalyst converter not to par, my mechanic however said he'd do it for around 800 but that it wouldn't hurt it to continue to drive it, that I would just have worse gas mileage. Oklahoma doesn't have emissions testing, but I plan on getting it fixed soon. I have over 160,000 miles on it. I guess this is just a common problem. one problem after 160,000 miles, better than other brands of cars.
Bart Iowa City Iowa

Iowa City, IA

#63 Apr 5, 2010
What is the with the "reliability and loyalty" ads? When catalytic converters go bad before their time, the value of the car goes down $1200 whether or not it is under warranty--reliability?
When one of the seven autos your family has purchased from the same dealer has the catelytic converter go bad way before other models and the dealer says "to bad-warranty expired," where is the loyalty? I guess loyaly goes only one way.
TANAKA

Laurel, MD

#64 Apr 6, 2010
Skuby wrote:
What if you clear the check light right before the smog test. Will would it pass???
It will probably fail. I had 191k on mine and replaced the front 02 sensor and the NOX was too high. The cat has to be replaced. I'm still looking for a cheap cat.
Rosalind

Fairfax, VA

#65 Apr 6, 2010
I have a 2003 Toyota bought it and 02 brand new mind you...I also have the cat problem. The car didn’t pass inspection recently for this reason. Well partially for this reason (KOER and MIL failed) my mechanic quoted me a $2100.00 price which I believe maybe a bit steep from the comments I’ve been reading. I wish we could all get together and make Toyota fix our 2003 Toyota corolla’s because obviously there was a problem with the yrs catylic converters.
Steven Leighty

Ventura, CA

#66 Apr 6, 2010
TANAKA wrote:
<quoted text>
It will probably fail. I had 191k on mine and replaced the front 02 sensor and the NOX was too high. The cat has to be replaced. I'm still looking for a cheap cat.
High NOX emissions is probably not the Cat converter. That would be your EGR valve or equivalent i believe.
Steven Leighty

Ventura, CA

#67 Apr 6, 2010
A 50 state legal cat converter should work. I will be trying it next week. It might also help to space the rear O2 sensor out with the ebay adapter as somebody else suggested. I think you might be able to use a spark plug de-foulder instead also.
Kenny G

Nashville, TN

#68 Apr 26, 2010
The CEL on my 2003 Corolla started coming on a year ago. Got the usual story about how I needed a new Cat and ECU reprogramming for a cool $1200. I spent a week in Florida last summer using different gasoline and wa-la the light goes out. Drive back to Tennessee with Florida gas...no light. Fill up with Tennessee gas and, you guessed it light is back on in 15 miles. IT AINT THE CAT, its the GASoline with the freaking 10% ethanol mixture. My 2001 Honda is doing the exact same thing. So I employed a fix I found on Honda site that costs $8.00 and it works! After 1000 miles, CEL is off, fuel economy & performance are back. Link listed below. Git er done!

http://www.honda-tech.com/showthread.php...
Kenny G

Nashville, TN

#69 Apr 26, 2010
Steven Leighty wrote:
A 50 state legal cat converter should work. I will be trying it next week. It might also help to space the rear O2 sensor out with the ebay adapter as somebody else suggested. I think you might be able to use a spark plug de-foulder instead also.
The CEL on my 2003 Corolla started coming on a year ago. Got the usual story about how I needed a new Cat and ECU reprogramming for a cool $1200. I spent a week in Florida last summer using different gasoline and wa-la the light goes out. Drive back to Tennessee with Florida gas...no light. Fill up with Tennessee gas and, you guessed it light is back on in 15 miles. IT AINT THE CAT, its the GASoline with the freaking 10% ethanol mixture. My 2001 Honda is doing the exact same thing. So I employed a fix I found on Honda site that costs $8.00 and it works! After 1000 miles, CEL is off, fuel economy & performance are back. Link listed below. Git er done!

http://www.honda-tech.com/showthread.php ...
liner

Bronx, NY

#70 Apr 27, 2010
Kenny G wrote:
<quoted text>
The CEL on my 2003 Corolla started coming on a year ago. Got the usual story about how I needed a new Cat and ECU reprogramming for a cool $1200. I spent a week in Florida last summer using different gasoline and wa-la the light goes out. Drive back to Tennessee with Florida gas...no light. Fill up with Tennessee gas and, you guessed it light is back on in 15 miles. IT AINT THE CAT, its the GASoline with the freaking 10% ethanol mixture. My 2001 Honda is doing the exact same thing. So I employed a fix I found on Honda site that costs $8.00 and it works! After 1000 miles, CEL is off, fuel economy & performance are back. Link listed below. Git er done!
http://www.honda-tech.com/showthread.php ...
I'm curious, but your link doesn't work.
Kenny G

Franklin, TN

#71 Apr 27, 2010
liner wrote:
<quoted text>
I'm curious, but your link doesn't work.
It did that last night too. But then started working. Keep trying. If I can get on, I will copy and paste it into this site.
Kenny G

Franklin, TN

#72 Apr 27, 2010
Kenny G

Franklin, TN

#73 Apr 27, 2010
I tried to copy and paste but this site wont allow the photo's. They make the instructions much easier to grasp. Copy of verbiage is below.

O2 Cell Fix

notes before starting
- you might have space for only 1 spark plug anti-fouler, sometimes using 1 will work / sometimes not
- having an electric drill helps out tremendously , those battery operated ones dont have that much power; they will still work but will be a pain
- this may still not solve your problem of the light; a small amount of people that try this 'quick fix' still cant get the light to go off

STEP 1
-purchase 2 spark plug anti foulers at your local auto parts store
-18 mm size
-made by HELP brand / part number 42002
-HELP has also another part number 42009 and are shorter in length than the 42002, i have heard they worked , but i am not 100 percent

STEP 2
-disconnect the negative terminal on your battery. this will reset your ecu
-take one of the anti foulers and drill out its center using a 1/2 bit ,
-this will increase its hole size and allow your stock o2 sensor to fit

STEP 3
-screw the drilled spark plug anti-fouler on top of the original
-be sure to use some kind of anti-seize on the treads. in case you need to remove your fix with ease

STEP 4
-unscrew your stock o2 sensor and place your cel / ses fix in
-use anti seize on the threads
-clean your cell (by wiping it off with a paper towel)

STEP 5
-reinstall your o2 sensor
-use anti seize on the threads

STEP 6
-reconnect your battery (your ecu is reset)
-you have just solved the problem of the 'damn light keeps coming on'
Kenny G

Franklin, TN

#74 May 2, 2010
1200 miles later the CEL is not illuminated.
Kenny G

Nashville, TN

#75 May 11, 2010
2000 miles and no CEL.$8 and 45 minutes sure beats $1100. Kenny likes it!!!
jimmiejay

Saint Louis, MO

#76 May 18, 2010
Skuby wrote:
What if you clear the check light right before the smog test. Will would it pass???
yes
Edwin

United States

#77 May 19, 2010
I thought it was way too expensive when my mechanic said $513 to replace my catalyst converter. But after reading this blog, I think I'm getting a really good deal.
ford tech

Henderson, NV

#78 Jun 13, 2010
Sharon wrote:
I have a 2003 Corolla and have had it since 2002, brand new....and have never had any problems with it before. I bought it because I wanted to buy something that was very dependable for the price.
I've been told that I need a new catalytic converter. About 3 weeks ago my "Check Engine" light went on. I took it to my mechanic (who I totally trust, btw) and they hooked the car up to see what the problem was. It was the converter, isn't running up to par. They tried cleaning it out and said that may have fixed it. But now the Check Engine light went on again. They said if this happened I'd probably have to replace it.
Isn't it unusual for a 6 year old Corolla to have this problem? It's an expensive one to fix, but I feel it's worth it because I could have many more good years from this car.
Just a little heads up but in NV if you clean out your cat and admit to it its a 10,000 dollar fine.(just a heads up) but they would have to find out first.
ford tech

Henderson, NV

#79 Jun 13, 2010
You cant clean out your cat it is illegal to do that. while it is almost impossible to prove (besides having a statment up that says it)in NV it is a 10,000$ if they find out.
liner

Bronx, NY

#80 Jun 13, 2010
ford tech wrote:
You cant clean out your cat it is illegal to do that. while it is almost impossible to prove (besides having a statment up that says it)in NV it is a 10,000$ if they find out.
Not sure what you mean about "cleaning out" the cat. Do you run some chemical thru it? I imagine the fine would be for "tampering with an emission device".
Scroom. Do what you gotta do to fix the problem.
Bridgette

Wilson, NC

#81 Jun 25, 2010
Disconnect your car battery for a couple minutes. The engine light will turn off - but don't get too excited - the computer will give out a "not ready" message upon inspection. So, hop in the car and take a nice little trip to a neighboring town via the highway, you'll need to put some miles on your car so the reading won't be blank. Find a local mechanic in town and see if your car will give the necessary reading. If not, drive home to your own trusted mechanic and try again. Hopefully the light will still be off at this point. If it IS off but STILL "not ready" explain your situation to the mechanic and drive around town for several more miles before coming back.(If said mechanic finds your returning trips too tedious, you can also stop to get an engine light reading at Advanced Auto or Snappy Lube-type places.)

I had the whole cat convert replaced for $1400 and the light came on a few weeks later. Infuriating. The above little game is the only way I know to get through inspections each year. Honestly, I'd try it before spending any money on repairs. Even the individual sensors cost a lot. If it doesn't work this first time, your mechanic can give you a slip of paper that tells any inquiring cops you're working on the situation. This will give you another month.

BTW this problem (the 0420 code) doesn't effect the safety of your car - and doesn't even necessarily mean it is polluting the air any more than everyone else - so don't feel bad about barely sliding through emissions inspections.

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