What does this check engine code mean?

captain7 · 02-25-2008, 03:25 AM

My check engine light came on and the code reader at Oreillys states that the "catalyst efficiency is low in bank one". I am wondering O2 sensor before the cat or the cat itself. If it is the O2 sensor why doesn't the code state that?
Hey thanks to you all!!!!!
Jim (Fireman Jim)

tiFreak · 02-25-2008, 03:29 AM

sounds like it's the cat itself, careful when you replace it because a lot of aftermarket cats have been known to throw codes

captain7 · 02-25-2008, 04:53 AM

Thanks! I was affraid of that. I am not going to put a BMW cat back in it. The car has 199,600 miles on it and we got it for my daughter's first car. Since I only paid $500 for the car, I can't afford nor does it make since to pay $1,000 for BMW replacement cat. I will just live with the check engine light.
Thanks for the input!
Fireman Jim

CirrusSR22 · 02-25-2008, 05:00 AM

I've heard if you install a "no-foul" spark plug adapter on the oxygen sensor you can trick the system. I think it just pulls the oxygen sensor out of the exhaust stream a bit.

Also, have you checked to make sure the oxygen sensors are good? The Bentley manual has the testing procedure I believe. Otherwise, with 200,000 miles on the thing, I'd just live with the light as you said.

captain7 · 02-25-2008, 05:19 AM

I thought about the sensors but not sure how to test them. Plus, they cost $130 each, not in a big hurry to replace them.
Thanks!
Fireman Jim

marko · 02-25-2008, 03:05 PM

as long as the car is currently inspected, you should be fine.. but, you will never pass inspection in the future if you buy & install an aftemarket cat. they simply do not work.
good luck..

Quote:

Originally Posted by captain7

Thanks! I was affraid of that. I am not going to put a BMW cat back in it. The car has 199,600 miles on it and we got it for my daughter's first car. Since I only paid $500 for the car, I can't afford nor does it make since to pay $1,000 for BMW replacement cat. I will just live with the check engine light.
Thanks for the input!
Fireman Jim

tiFreak · 02-25-2008, 03:44 PM

Quote:

Originally Posted by captain7

I only paid $500 for the car

wow, looks like someone can't brag about the price on their car anymore

mohaughn · 02-25-2008, 08:19 PM

Quote:

Originally Posted by captain7

I thought about the sensors but not sure how to test them. Plus, they cost $130 each, not in a big hurry to replace them.
Thanks!
Fireman Jim

You can get a generic Bosch O2 sensor much cheaper. It will be the same exact sensor, just has the wires coming out without a plug. Take your old sensor, cut off the plug, solder/wire wrap the new plug on, and you are good to go.

Saves about 100$.. Do a google search for the code number that was pulled. You can usually find exactly what the code means.

OBD codes are generic to all cars that use the OBD system. That is why they are not more specific.

ClubSport · 02-26-2008, 01:44 AM

Seriously, don't replace the cat until you eliminate the O2 sensors as culprits. All this code is saying is that the oxygen content after the cat is not what's expected. Could be a bad cat, but much more likely a bad value coming from the post-cat sensor. Search the web for the blowtorch method of testing them.

captain7 · 02-26-2008, 05:05 AM

Thanks guys. We bought the car as a first car for my daughter. I could have been that lucky to have a car like this when I was 16. But, being a 96 model with that many miles is saving us $100 a month in insurance. Yes you get what you pay for. Inspection procedures in Missouri are not that strict. I have already had 3 garages tell me that they do not take any readings on the cat. As long as it is there, is good enough.

Thanks for the sensor info. I will look to see what kind I have, then purchase one that I can just cut off the end and solder a the old end on. They look like they are running ball park $50. I was told that the code "bank one" means the sensor before the cat. So that is my first victim.

We may have to just get used to the rattling noise from under the car and the "check engine" light being on. Kinda like my first car or truck being a bug fogger. I got used to it.

Now I am bragging. The car doesn't smoke, leak or otherwise use oil. The only rattle is the exhaust system. If I let go of the steering wheel, the car tracks straight. Nor does it pull when the brakes are applied and it stops. It takes turns and bumps great with none of the suspension system showing wear or leaks. The body has only one small dent with no rust. The tires are not worn especially unevenly. So we did get our $$ worth, except for this cat thing. If anything, we can save the $$$ and repair later.

I can't express enough how much this newbie appreciates all this help and the nice comments. I can take any rubbing especially the bragging about my $500car. Keep it coming, cool to read all this.
Thanks again!!
Fireman Jim

thesk8nmidget · 03-06-2008, 01:17 AM

thats awesome you scored such a good deal... is there a story behind this??

and also how bout some pictures???

welcome to the forum and hope the sensor is the only problem.

anthonyl · 03-06-2008, 01:43 AM

I just failed my emission test today with the same fault code. So I went home pluged in my peake code reader and sure enough 28 poped up. So I reset the fault code and drove around for 30 min. I checked to see if any codes were showing after my fun drive and there were none. hahaha, I giggled like a little school girl with crush.

JNCoulombe · 03-06-2008, 03:01 AM

You may still trigger a code again when driving under different conditions. I had this happen to me repeatedly until I changed the front O2 sensor. Driving at low rpm would trigger the low catalyst efficency code. I would clear the codes and drive for quite awhile until enevitably I'd get caught in traffic and trigger the code. I was convinced it was the catalyst, since I had replaced the O2 sensors 50K miles previously. The emissions testing station wouldn't pass the car even with the codes cleared unless the car has been driven a sufficent number of cycles. Fortunately, replacing the front sensor cured the code problem and increased my gas milage. Worth a try (and not difficult) before you replace the catalyst. Also, I suspect any shop would insist on replacing them even if they were replacing your catalyst.

captain7 · 03-06-2008, 03:25 AM

I now have a different code. It now states "O2 sensor reading is slow bank 1 sensor 1". That is a pretty good evidence that it is the sensor.

Yea there is a story. My Brother-in-law bought this car 2 years ago, to rebuild. They built a house in a subdivision and with no knowledge, they have a covienant that any car in the driveway must be a daily driver. Will instead of getting rid of it he wanted to keep it in the family so he sold it to us to give to my 16 year old for her first car. We paid for the repairs and car and presented it to her for christmas. I wish I had a car like this when I was 16!!!!!!

I will try to post a picture as soon as my digital camera is repaired.
Thanks all!!! This is such a great site!!!
Fireman Jim

anthonyl · 03-06-2008, 04:52 AM

My plan is to reset the computer at the emissions testing place if needed.

.	Powered by site supporters vBulletin Version 3.8.8 Copyright ©2000 - 2024, Jelsoft Enterprises Ltd. Copyright ©1999 - 2024, 318ti.org © vBadvanced CMPS v3.2.2 [page compression: 115.26 k/138.10 k (16.54%)]
318ti.org does not warrant or assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information or products discussed.