I have a 1998 ES300 with 160K on it. About six months ago, I developed a hole in the exhaust and found that it was in the section that includes the catalytic converter. The local muffler shop replaced it with an after market converter. Everything was fine for about three months then the check engine light came on followed a couple of days later by the Trac Contol light.
I went to the Lexus dealership and was told that it was a P0420 code that meant that the converter was not functioning properly. They offered to put in an $1800 OEM converter and I politely decline as that would be 80% of the current value of the car. I also asked why the traction control would be turned off because of emmision problems. They did not have an answer. Next I went back to the muffler shop and they replaced the converter on warranty. They noted that there was soot in the exhaust pipe and said that it may be running too rich. I took it to a garage and they tested the car and said that it was not running rich.
Another three months passed and same problem all over again. So do I just live with no traction control (not the best idea in Minnesota).
I should also mention that I have had other electrical problems:
1. The light indicating that a tail light is out is on all the time. Lexus says that this is because I used the $1.29 auto shop bulbs instead of their $5 bulbs.
2. The security system goes off periodically for no apparent reason.
Thanks for any thoughts on what to do
