Catalytic Converter Rx300

[cuball]

Does anyone know when the Catalytic converter should be changed on a RX300?

Mine seems to have gradually lost power and I'm trying to pin point the problem. This is the first thing that comes to mind. I have 75,000 miles on the original converter.

Any ideas of the cost?

[monarch]

Toyota catalytic converters last between 100,000 and 500,000 miles depending on many variables. To maintain like new power and fuel economy and for long catalytic converter life the spark plugs should be changed twice as often as recommended in the factory maintenance schedule and the oxygen sensors should be replaced around 100,000 miles. The spark plug wires should be changed about every 75,000 miles. The throttle body plate should be cleaned about every 30,000 miles.

So in your case you're due for new spark plugs and plug wires and cleaning of the throttle body plate http://www.saber.net/~monarch/tpcleaners.JPG. Your catalytic converter is probably fine.

[dgorrie]

I would think that to lose power and the catalytic converter be the causer, the catalytic converter would have to be clogged up. I have to think that is pretty unusual these days.

A more likely cause is the air mass meter. Mine started acting up, causing loss of power, then the Check Engine finally came on after 2-3 weeks. Could also be the O2 sensors.

Several folks on this forum have just pulled the air mass meter out, cleaned the filament with carb cleaner, then put it back in. That's worth a shot. It has two screws holding it in, somewhere behind the air filter. along with a simple electrical connector. I secured a replacement for my car ('99 RX300) at http://newlexusparts.com for around $115.

How long has the problem been going on?

[cuball]

Well it's a funny thing. Its seems to have become an issue when I purchused my Toyota Tundra with the I-force V8. Maybe there is nothing wrong with the engine. My wife and I may have just become spoiled by the horsepower from my new truck. Although its only about 40 horses more than the RX, it does have a lot more torque.

I haven't seen any engine light come on at all. So I don't think its the O2 sensor. But the tuneup with a set of new plug wires sounds like a good place to start. I think I can eliminate the converter.

BTW, I just had the 60m maintance performed on the vechicle about 3 months ago. Wouldn't they have changed the spark plugs then? I guess I can go thru my records to see if they were changed.

[sgriffith]

I had my plugs changed at 70K and the dealership told me that I didn't need them changed until after 90K miles.....so I am sure they didn't under the 60K service unless you asked them to. I went ahead and had mine changed anyways though.

[wwest]

In my experience the most common thing is for chunks of the catylist honeycomb structure to come off and then partially block the exhaust. In all cases of this I am aware of the exhaust upstream of the converter would glow cherry red after driving a relatively short distance.

The Tundra might be a really poor comparison since trucks typically have a much lower first gear and final drive ratio combination. Also of note is the fact that even the new RX330 will feel more "torquey" with the new 5 speed which also has a lower 1st gear ratio and at least one of the AWd RX's final drive ratios is also lower, 3.48 vs ~3.12.

Also remember that since the RX is predominantly FWD the VSC system will often step in and limit engine torque to prevent impending wheelspin at the primary drive wheels. With the Tundra being RWD the VSC is not ikely to intervene since with rear wheelspin you will have directional control.

[SKperformance]

might be able to tell if you mentioned the year and mileage

??

[monarch]

In my experience the most common thing is for chunks of the catylist honeycomb structure to come off and then partially block the exhaust. In all cases of this I am aware of the exhaust upstream of the converter would glow cherry red after driving a relatively short distance.

Is your experience with disintegrating converters Toyota experience or experience with other car makes?

Toyota converters are costly, but extremely durable if not abused. My '91 LS400 has almost undetectable hydrocarbon and carbon monoxide emissions after 101,000 miles which means the converter is not hardly worn yet. My '92 Toyota pickup has 448,000 miles and still passes the tough California smog tests with its factory original cat converter: http://www.saber.net/~monarch/448.jpg On the "Toyotas-Only" yahoo discussion group a Toyota shop mechanic knows about one Toyota owner with over 500,000 miles on the original converter.

[wwest]

One failure was a Ford Pinto SW 2.3L I4/manual and the other was my 78 Porsche Targa.

If not abused....

If I remember correctly abuse in this "instance" is restricted to running too lean a mixture. Other than a manufacturing flaw or accident damage I don't know of any other reason for one to fail.

I bought the 78 in 83 with 37k miles so don't know much of the history before that. Bought the Pinto new but who knows with caburation.

[cuball]

might be able to tell if you mentioned the year and mileage

??

My first post says I have 75m on the vehicle. And the year is in my signiture at the bottom of the post.

Thanks for all the info everyone.

[SKperformance]

many members like myself turn off the avatar and sigs to increase page loading speed.