rdoine

Does anyone have a good source for the 02 sensors for a 95 SC400? I know the car requires several (at least 4) but I can't really identify the correct ones when I look at different online suppliers. Thanks for any help you can provide.

lexdud

The SC4 (at least my '93 has four (4) oxygen sensors:

#1 - Main O2 sensor for right bank
#2 - Main O2 sensor for left bank
#3 - Sub O2 sensor for right bank
#4 - Sub O2 sensor for left bank

All four sensors should not have to be replaced. Why are you planning to replace them all at the same time?

The O2 sensor can be found at many different places including Autozone and ebay. Yuo can find them for about $30 each on fleabay.

Good luck ...

rdoine

The car has 190K miles on it and it has never had an 02 sensor or exhaust piece replaced. I am going to start with replacing the 2 main sensors but I don't know which ones to buy, 4 wire, 3 wire, 2 wire. I guess Autozone can tell me what the correct ones are. The car is running so poorly (fuel mileage) that I need to get something done or park it.

lexdud

You might consider doing what I did ... go to the dealer for a diagnostic. I know, we hate going to the dealer but for $120 they provided a pretty accurate diagnostic of what was wrong with the car. If I had chosen to get it fixed through them it would have run $2,200 plus labor. Instead, I walked with the diagnostic report in-hand, bought the parts myself (used) and fixed the car in my garage for a small fraction of what they wanted.

Unfortunately we cannot fix everything on our cars ourselves ... but knowing what the problem(s) are ... is the first step to fixing them. You could spend hundreds if not thousands of dollars replacing parts you THINK are bad instead of what is actually bad.

Good luck ... I've been where you are ... and it's no fun.

rdoine

I had the car checked out at an independent shop. The print out shows an exhaust system failure requiring all cats and o2 sensors needing replacement. I have a lift so I can do a lot of the work myself. I just want to make sure I get the correct parts before I start the project. I think I'll start with the front sensors and see what happens. Then, I'll move on to the cats and subsequent sensors. At 190K miles, I shouldn't be surprised at needing quite a bit of work. Thanks for your suggestions and input. Any other thoughts will also be appreciated.

BostonSC4

iTrader: (2)

were there any check engine lights on? and you should go with magnaflow hi flow cats if your into that at all, just since your rippin them out anyways might as well throw in something good = )

rdoine

Good question. I was out of town when all this happened. But, I have not seen any CE light nor did my wife or daughter mention them. But, the car is running very rough. I'm going to replace the front 02's and then see what happens. I'll take it a step at a time. Thanks.

Dx3

iTrader: (13)

It sounds like you are throwing parts at a problem that hasn't fully been diagnosed. A bad )2 sensor will throw a code. A bad cat will throw a code. If you have no CEL then I would look elsewhere - primarily a full tune-up.

Jonny

rdoine

Thanks. The diagnostics that I got point to cats, sensors, and tune up. I can't get to the work needed right now due to my travel schedule and the cold weather so I was going to change the front sensors to try to buy myself time till the weather gets a bit above freezing. But, you're right.

Dx3

iTrader: (13)

Before you do anything let's pull the codes and find out exactly what codes you are throwing. It is a simple process that just takes a couple of minutes.

Grab a paperclip, and find the diagnostic port under your hood. It is a little black box. I don't remember where it is on an SC400. On the SC300 it is to the right of the intake manifold and says "Diagnostics" on it. From there, grab a paperclip and bend it into a "U" shape. Place one side in the "TE1" terminal and the other side in the "E1" terminal. Now go inside your car and turn the key to on (Don't start car.) Count the number of flashes, then a pause, then count the number of flashes. The first set of flashes relates to a set of 10, while the second set related to single digits.

For instance:

Flash, flash, flash....pause, flash = 31.

That is your code. Do that and get all of your codes and let me know and I will check them out for you. Good luck,

Jonny

rdoine

That sounds pretty slick and simple. I'll try to do it yet this weekend if I can brave the cold. Might not get it done till later in the week since I have to leave again Sunday. I'll get them to you as soon as I can. Thanks very much.

rdoine

I found the diagnostics connection but I cannot determine which of the connections are the "TE1" and the "E1". There are two connectors that sit higher than the others but there are a number of other connections. I suspect making a mistake would not be good.
BTW, the CE light goes out upon start up, as it should. There is no CE light while the car is running. If I can determine the correct connections, I'll get the codes to post.