Hello guys im new to this forum, i bought this 2000 300 for my mom 3 years ago with only 87000 miles, about a year later i replaced the timing belt, both front a/f sensor with lexus/toyota part numbers and replaced both vvti oil sensors, about 2 weeks ago my mom called me and told me check engine light was on, i took a trip to Daytona where she lives and picked up the car and brough it over to my house on Palm Beach, car drove fine with no issues.

after reading the codes p1135, p1155 codes came up, now at this time i was like the sensors have only about 13000 miles of use, but i went ahead and order all 3 new a/f sensors with the denso ones and replaced them and after a few driving cycles lights came back, now while i was installing the sensors i noticed that someone did some work on the car i then called my mom and she told me that a repair shop replaced the valve cover gasket because it was leaking oil.

i ask her if the light was on when she took it to get the oil leak fixed and she told me that it wasnt, and that the light came on a couple hours after leaving the shop.

does anyone have an idea what else could be wrong, i know those two codes have to do with the heater on the sensor, but im not really that good with electrical, i also switch the relay and checked the fuse for the sensor heating circuit and check out ok.

 

Are you related to 2ks?

 

Art, you old rabble rouser.

 

Boost, what EXACT codes came up? Did both P1135 and P1155 come up seperately? Meaning when you run the codes your scanner or reader shows "2 codes"? For one thing those are indeed both heater codes and you should be able to easily check the heater circuit to see if the heater circuit shows burned out or not. (This is on the sensors.) It would be extremely unusual for both DENSO sensors to fail in that short a time. What is the part # of the Denso sensors that you installed 13,000 mi. ago and did you use the same part # Denso this time? I strongly suspicion that the sensors MAY not have actually been bad either time. People are to quick to take the DTC's as gospel, and they simply are not. They are at best, an aid to help you in the right direction to TRY to actually determine what is wrong (if anything!) Don't throw parts at CEL's, you'll be throwing a lot of money, (and good parts) away if you do.

 

nope im not related to 2ks in any way.

 

when i read the codes 2 codes come up 1135 and 11555.

the first sensors that i installed 13000 miles ago are original lexus sensor, this time i replaced the oem sensor with the denso part number given in this forum, i got them from amazon plug and play.

and yes i didnt think both sensors could have being bad with only 13000 miles on it, but it was the fastest way for me to see if that would fix the problem, so i blew 200 dollars away, and now have 2 low miles toyota/lexus sensor for spares.

which wire should i test, and how do i do it.

Thanks

 

Boost, when you say you switched the relay what does that mean? Did you put a new relay in or just switch with another relay? Also, when you say you checked the fuse, did you remove the fuse, did you visually check it or did you check it with a volt meter with it in place to check for continuity? I ask all these questions for a reason. I always hate to hear when light comes on shortly after leaving a shop, because I think most of the time it's more than a coincidence.