Hello everybody,
I seriously need your help guys & i thank you all in advance. First of all i am from Toronto, Ontario, Canada i got 2000 GS400.....i got this car 14months ago....my engine check light was on so i took my car to a Lexus dealership for inspection. they told me that it's the both catlyst convertor in my car they are both below the threshold level and need to be replaced....now the dealer also told me i dont have to replace them until i feel that i am loosing power...but i dont wana waite i wana get it fixed i mean when you know there is something wrong you know what i mean now each part is $700.00 so for 2 catlyst convertors $1400.00 plus the labour......i always take my car to dealer for service and use high quality gas also....not sure what to do at this point...i have been advised that catlyst convertor's are made for the life of this car and it is next to impossible that both of them gone bad and need replacement. i even did the fuel system cleanup but the light still comes on and goes away....can you guys please HELP.....any suggestion or advises......i mean maybe buy part from dealer get it done from a good shop or maybe if you guys can tell me some place i can buy lexus parts from and then have the dealer replce them.....any help would be appreciated as i am lost....once again Thanks in advance....

 

This's very rare case to see the cat. on the GS400 goes bad. I
ve seen them goes bad on the 95-96 LS every once a while,but not on the GS.

Code P0420 and P0430 Catalyst efficiency below thresholds bank 1 and 2 usually set the CEL when the reading of the O2 before the cat and the O2 after the cat won't match their pre-set.

Contact Carson Toyota or Sewell Lexus for the price or post WTB in the classified forum for the heck of it. Good luck.

 

make sure you do not have any exhaust leaks before the secondary o2 sensor, they will also set the code.

 

make sure you do not have any exhaust leaks before the secondary o2 sensor, they will also set the code.

 

Also, you only HAVE to keep the cats for 7 years or 70k miles....whichever comes first. After that, if they fail, you can take them out and not replace them. So assuming you've crossed one of those thresholds, you can just take it to any muffler shop and have them bend a new straight-through pipe for you. Should only cost a couple hundred at most.

 

Sorry, why only 7 years and why would they not be needed thereafter?

 

Where is this law? Im pretty sure its against any emission laws in any state to remove cats, no matter how old the car is.

Also, i had a 98 GS400 a while back, and both the cats on that car went bad as well. Its rare, but it happens. Maybe the previous owner used bad fuel. There are aftermarket replacement options available, rather than going with toyota/lexus parts. You could probably save 50% on the price of the parts, easy. There will be almost zero difference in the quality.

 

Correct... to the technical letter of the law, it is illegal to remove any emissions component unless it is to replace it if it is malfunctioning... This includes catalytic converters... does that mean that this happens just this way, absolutely not, but, it needs to be said correctly...

The EPA regulations also say that for 8 years or 80k miles, the catalytic converter is covered under warranty...

 

have you tried a cat cleaner?