LSPiNoY

iTrader: (1)

my LS drives fine. the only problem is that since the weather has been getting warmer, the check engine and trac light come on every so often. when i slow down to a stop the enging light would go away, but the trac light stays on. when i shut the engine off and turn it back on it goes away. whats the matter with my lex? is it a sign of old age? lol hope not. anyone have any ideas as to what is actually causing this?i would like to know. thanks

dbullen

iTrader: (3)

O2 Sensor possibly?

rajah996

Most likely O2 sensors.

-R

LSPiNoY

iTrader: (1)

why what is it doing? so this item needs to be replaced? please give me some more insight and recommendations thanks.

rajah996

It sounds like one of the four O2 sensors is ready to kick. If one of your sensors
is giving an incorrect reading, or no reading at all, it will kick of the trac control.
It will also set off the check engine light. Having had the problem before, I can
tell you this problem happens intermitently. I would take it to a mechanic or
Lexus to have them check it out. THey should be able to tell you specifically if
it is an 02 sensor, and which one. Also does your exhaust smell funny?

-R

LSPiNoY

iTrader: (1)

thanks for everyone's help. i will smell it tomorrow. if there is something wrong, then the exhaust fumes would smell like something burning?? the normal scent would smell like gasoline smoke right?

rajah996

The smell is kindof like something foul. I would say either
rotten eggs, or paint thinner, trust me, if your car has it, you
will know. lol
Hope this helps.

-R

LexLS

I know that smell, it's horrible. A friend of mine had that on her 2002 Jetta, she couldn't figure out what was wrong so she just sold it, hahaaa! Anyway, it's good to know that the O2 sensor may be to blame. I don't want to sell my car if I encounter this.
Earl!

TomWahjudi

Rarely it's the cat that went, usually it's the O2 sensor that went first. I'm driving around with check engine light on because one of the two downstream O2 sensors is broken. Although my TRAC light doesn't light up. Before I bought the car, the check engine light and TRAC light were both lit. It turned out one of the spark plug wires was loose. I can't say that it's the cause in your case, but at least bring it to Autozone and have them retrieve the code(s). Good luck.

Lvangundy

There's 4 oxygen sensors which connect to the exhaust section of your car. They screw into a hole in the piping.

2 of them are located after the manifold but before the catalytic convertors (cats)..

Well definetly the other two are located after the cats. The function of these is to check the make sure the other sensors are working.

Each O2 sensor (toyota brand) will cost about $100.

Here's a quote from an online seller..

The Oxygen Sensor measures the oxygen content of the exhaust. Most OEM's recommend checking or replacing the Oxygen Sensor at 25,000 to 30,000 miles. A faulty sensor can damage the converter so the Oxygen Sensor should be checked if the converter has melted down. There are two types of Oxygen Sensors in use: The Zirconia type which generates a voltage in response to exhaust heat and oxygen content, and the Titania type which varies its resistance in response to exhaust heat and oxygen content. These Oxygen Sensors are NOT Interchangeable. Please consult your sales representative for the proper unit.

TomWahjudi

Lvangundy,

The downstream O2 sensors are there to check if the cats are in working order. The upstream O2 sensors are used to control a/f ratio. In any rate, where did you find Toyota (genuine parts I take it ?) O2 sensor for $100 ? I have been quoted for more than that.