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Discussion Starter · #1 ·
Check engine light is on, reputable shop pulled codes and said it needed new cats and to replace oxygen sensors. I want to sell the car but need to reflect this repair in the price.
 

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Check engine light is on, reputable shop pulled codes and said it needed new cats and to replace oxygen sensors. I want to sell the car but need to reflect this repair in the price.
Then it is an "as is" car and that reduces the price more than the price of the parts. If you can you would be better to fix those things, but I really doubt the cats need replacing. I would need the codes but that sounds like a very poor diagnosis by someone that does not really know these cars. 4 O2 sensors are always a good thing, but further diag is needed.
Frankly I have bought many a car like yours in the past and the price is "what the seller will take" not really related to the market, selling or buying an "as is" car is a little bit of a mugs game.
 

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codes 179, 012, 145
Bad diagnosis, without a doubt. The right answer is we have no idea what is wrong and we have to check a bunch of things. The 145 tells you that the fuel trim for that bank has been adjusted to it's max and is likely turned up to add extra fuel. If there is not enough air and too much fuel that will cause your cat code, 179. Why you have the 145 code could be many things that need to be looked at. The 145 might have something to do with the 012 or the 012 might be causing the 145, again things need to be tested.
Do you do any work on the car or only take it to someone? If you can do work I can explain the basic tests and things to look at, but if not you need to find a better shop. These cars can be worth a few bucks depending on the rest of the condition so it might be worth fixing this if that is all that is holding the value down.
 

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Discussion Starter · #8 ·
Bad diagnosis, without a doubt. The right answer is we have no idea what is wrong and we have to check a bunch of things. The 145 tells you that the fuel trim for that bank has been adjusted to it's max and is likely turned up to add extra fuel. If there is not enough air and too much fuel that will cause your cat code, 179. Why you have the 145 code could be many things that need to be looked at. The 145 might have something to do with the 012 or the 012 might be causing the 145, again things need to be tested.
Do you do any work on the car or only take it to someone? If you can do work I can explain the basic tests and things to look at, but if not you need to find a better shop. These cars can be worth a few bucks depending on the rest of the condition so it might be worth fixing this if that is all that is holding the value down.
This is supposedly one of the best shops in Atlanta, GA
 

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This is supposedly one of the best shops in Atlanta, GA
Those types of shops are usually skilled at reaching into your wallet. Did they give you a quote? Here is the narrative, they quote you 5k knowing you either have a bad injector or vacuum leak and the O2. They spend an hour figuring it out and fixing it. When you arrive they say good news she is all fixed and for much less. Hand you a bill for 1800 which you gladly pay because it is way less than 1/2 the quote. Reality is the job you paid for was really only 2 hrs work and a couple hundred in parts maybe 800 on the generous side. Leaves you feeling like they are the greatest but they grabbed an extra grand profit. Yes a little cynical, but I have been around in that industry for some time.
The shop I would be using is the one that tells you the truth and gives a recommendation that will help you in the long run. All your O2s are likely original and at the end of their lives, I would use the guy that says lets replace all four O2s and get some real readings but I know you might have a air fuel issue so let me take a fast look might find something, but lets replace the O2s and drive it for a week and we will see what happens.
 

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Check engine light is on, reputable shop pulled codes and said it needed new cats and to replace oxygen sensors. I want to sell the car but need to reflect this repair in the price.
Hello john3,

Food for thought. In a few years (depends on your M.Y.) car will be exempt from emissions standards. AKA, no need to replace cats, delete cats and MIL through software and drive w/o issue.

Light to medium airplanes are still using fuel with Lead! All piston engine planes are exempt from "no lead" law required by passenger vehicles. 25yr old cars with good upstream o2 sensors and no CATS much preferred!

just my thoughts for fun,

P-Chi
 

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I can pretty much guarantee you that the cats don't need to be replaced. You DO probably need some preventative maintenance done which includes "precat" O2's.
 
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Bosch are the same no matter where you buy them, Amazon works but maybe your local parts store will be the same price with no delivery. Your one code makes it absolutely clear that one pre cat is faulty. Replacing as a pair is the smart thing considering the age. You should save yourself the grief and cost of doing it twice though. The Cat code you are getting is a result of the comparison of post and pre cat sensors. Even though there may not be a code for the posts a fault there has often given a false cat code although normal failure reports more O2 than there is which is the opposite of a cat code. At a 100k that is all the life they have. If I only had 300 to spend on this I would buy four after market and install rather than only two Bosch up front considering the cat code and age. Really I would find the few bucks more and put 4 Bosch in.
 

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I am just going to add to the O2 sensor replacement. 2 or 4 your choice, your money, your car. The also step which must be done with care is the bungs that hold the O2 sensors must be inspected very well for cracks. They need to clean them and look with a magnifying glass. It is not a common problem on this car, being 1 in 10 but likely it would be fair to call it frequent and 1 in 100 cars have it happen. the cracks even if very small will such air in and throw the O2 reading off and the car will add fuel to that bank. You also need to go back up from the O2 sensor to the engine and confirm there are no leaks in that part. Leaks in the exhaust before the pre cat O2 represent a large percentage of the cause for a single bank running richer than the other bank.
 

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Discussion Starter · #16 ·
I am just going to add to the O2 sensor replacement. 2 or 4 your choice, your money, your car. The also step which must be done with care is the bungs that hold the O2 sensors must be inspected very well for cracks. They need to clean them and look with a magnifying glass. It is not a common problem on this car, being 1 in 10 but likely it would be fair to call it frequent and 1 in 100 cars have it happen. the cracks even if very small will such air in and throw the O2 reading off and the car will add fuel to that bank. You also need to go back up from the O2 sensor to the engine and confirm there are no leaks in that part. Leaks in the exhaust before the pre cat O2 represent a large percentage of the cause for a single bank running richer than the other bank.
Shoot me an email? tade_f at hotmail
Sent e-mail to [email protected]
Will do. I ordered all (4) O2 sensors and will install them myself.
 

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will install them myself.
The cracks are hard to see but if you wire brush them with a drill you are looking for any sign of a black line. Then while you have it up smoke some paper and hold it very close with the engine running preferably at a higher rpm also but at idle too. Any movement in the smoke is a bad sign.
 

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Sounds like you already bought the sensors, but I highly recommend RockAuto. You can get all 4 Bosch sensors for less than $300 if memory serves. RockAuto purchase guarantees it will be a real Bosch part too. On Amazon it can be a crap shoot if it's legit Bosch or a fake.
 
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