99 RX300 with 105k miles
About 2 months ago the CEL came on, and I did the quick and easy and replaced the gas cap. Light stayed on.
Had the codes checked, P0171. Replaced the Bank 1 O2 sensor. Light stayed on.
Checked the codes again, P1135. WTF? Changed the MAF sensor. Light goes out!
3 weeks and 1000 miles later, light comes back on. P0440.
Since I've already replaced the gas cap, I figure that's not it. I do some reading on here, and find the suggestion to check the hose coming from the back of the air cleaner box to the metal tube running below the master cylinder. It's connected nicely. Any other suggestions?
My wife loves this car, and I'd like to fix the stupid light.
