My 2001 LS430 with 109,000 miles had the check engine light come on while driving today but there are no other symptoms. I of course rechecked the gas cap. I took the car on the highway and there are no hiccups or any shifting issues. I know I should check out the codes at my trustworthy mechanic, but is it unusual for the check engine light to come on and the car continues to run with no issues? I know oxygen sensors are a common issue, but would my car be running so good? I will be bringing my car in tomorrow morning but was curious about the light. Any help would be greatly appreciated. .

 

Do an MPG test, look for leaks under the engine. Air leaks that is.

 

I had the check engine light come on a few weeks ago yet everything acted fine. Took it in and they told me it was the cats starting to go bad. They said I would be fine for a while, but when I start noticing a drop in MPG and performance that I need to get them replaced. They also said to get it done at a muffler shop with aftermarket cats because the OEM cats are $1000+.

I also read that it could be a leak in the exhaust from corrosion. Some people said they had small holes in the Y pipe.

 

you can go to any parts store and they will scan it free.

 

UPDATE: Went to my independent shop and it turned out to be Bank 2 Sensor 1. I didn't have the time or incentive to leave and shop around for my own sensor so had to go with the Lexus part. Cost me $336 including tax. I'm sure I could have gotten it for half the price with a Denso OEM, but I have a relationship with this shop and didn't want to ruin it. Besides, if there were any issues whatsoever after the fix with my part, I would be screwed. I paid the extra for the guarantee and let the shop make their money. It could have been worse if I had gone to Lexus. Now I hope the other 3 sensors hold up...........

 

Anyone replace their 02 sensors with Denso OEM? How did they work out?

 

Took my 2002 sc430 with the engine light on to the dealer, they said the left cat was bad. Light came back on they said right cat is also bad and gave a new gas cap. Lights still on. Now they tell me the ECU needs to be replace. Light now stays on for a few weeks, then goes off for a couple days Every time ive gone to the dealer, I GET SCREWED. Any help would be appreciated. Thanks

 

I'd try to find a good independent mechanic. A seasoned Toyota mechanic would probably be easier to find. Also check out using a tech stream dongle to pull the codes yourself. You can check the history of the codes that were cleared and what codes are currently on.