Replacing the Engine Temperature Sensor
Rookie
Joined: Dec 2014
Posts: 59
Likes: 0
From: TX
@ lav, fyi, the brand on that sensor is Toyoda in Japanese, which most people, incorrectly, refer to it as TEQ. You can read more here along with some pics. http://japantravelcafe.com/japanese-...-2-toyota-logo Anything that has that logo on it is a quality product 
I appreciate the write-up, looks like I have another thing to add to the to-do list.
I appreciate the write-up, looks like I have another thing to add to the to-do list.
Lexus Test Driver
Joined: Mar 2007
Posts: 1,025
Likes: 13
From: McAllen, TX
I just want update that after about 250 miles the car just feels smoother and more powerful. I am also seeing a little better gas mileage. Actually, the best I have seen out of the car yet. Mileage changes with conditions of course but I can honestly say that I believe replacing the temp sensor has improved the efficiency and power of the engine.
Edit... So much power now look what my LS can do...
Edit... So much power now look what my LS can do...
Good idea. Try a bottle of the Dura Lube Severe fuel system cleaner too. It's twice the size to treat our 21 gallons of gas. I think it works well. Walmart has it for $10. I use it every 5k to help keep carbon levels down. Carbon building up on the tops of pistons and / or valve can cause pinging too. In the heat of Miami it's more an issue as you are experiencing. Are you running 93?
Last edited by Lavrishevo; Apr 27, 2015 at 03:09 PM.
Lexus Test Driver
Joined: Mar 2007
Posts: 1,025
Likes: 13
From: McAllen, TX
Good idea. Try a bottle of the Dura Lube Severe fuel system cleaner too. It's twice the size to treat our 21 gallons of gas. I think it works well. Walmart has it for $10. I use it every 5k to help keep carbon levels down. Carbon building up on the tops of pistons and / or valve can cause pinging too. In the heat of Miami it's more an issue as you are experiencing. Are you running 93?
Yes I use Shell V-power almost all the time, if not then BP or Chevron premium or some other Top Tier premium. I've run Gumout and a few other products through the car and never noticed a difference. I'm going to try the water decarbonizing method tonight and see if that does anything.
Lexus Test Driver
Joined: Mar 2007
Posts: 1,025
Likes: 13
From: McAllen, TX
No change with ambient temps. I notice it mostly at higher vehicle speeds. It's most noticeable with heavy throttle, during shifts between gears. Does it at high or low rpms. I've tried to find specific patterns when it occurs but can't find anything definitive. The engine just has a generally lousy feel to it, as if it's handicapped or clogged up, although it does idle well and seems to run smooth. My mechanic has noticed it several times throughout the last few years (during test drives for other issues) but never gave me any sure fire diagnoses, and suggestions have always been just to run some cleaners through the fuel system. A few times I've tried driving around and manually shifting the car to keep the revs high, and I've been able to make it knock really bad right after a down shift followed by heavy throttle.
Normally knocking gets worse the hotter the engine gets. Let us know about the temp sensor. Sounds like your putting that engine through its paces.
Edit: You know, another idea if it's not the temp sensor could be the oil control valves. Those go with age and are part of the vvti. I would take one out and seeing if they have carbon building up.
Edit: You know, another idea if it's not the temp sensor could be the oil control valves. Those go with age and are part of the vvti. I would take one out and seeing if they have carbon building up.
Last edited by Lavrishevo; Apr 28, 2015 at 06:22 AM.
Lexus Test Driver
Joined: Mar 2007
Posts: 1,025
Likes: 13
From: McAllen, TX
I thought about the OCVs but kind of ruled them out since I don't have any CELs for them. Also just had both timing tubes replaced in the variable timing system so I'm assuming they are in good condition. Temp sensor will be here in a day or two so we'll see.
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Lexus Test Driver
Joined: Mar 2007
Posts: 1,025
Likes: 13
From: McAllen, TX
Got the sensor replaced last night, I think it's solved my pinging and knocking problem. I took the car for a test drive and the engine is running noticeably better, I got into it several times and the power was smoother and the engine runs quieter. Seems to feel "healthier" with a lot less harshness/chatter when I'm on the throttle either lightly or heavily. Idles better too. I'll be driving about 60 miles more tonight so I will be able to really put it through it's paces, but so far so good.
I think I've had this pinging problem for a least a few years, sure wish I had replaced this sooner. It for sure should be a maintenance item done at the timing belt/spark plug change at around a 100k miles.
I think I've had this pinging problem for a least a few years, sure wish I had replaced this sooner. It for sure should be a maintenance item done at the timing belt/spark plug change at around a 100k miles.
Racer
Joined: Apr 2009
Posts: 1,358
Likes: 87
From: Delaware
I have wanted to do this for some time now. Mine has not failed nor do I have any codes but from what I learned from the a LS400 and the forums is they don't tend to fail like this. They basically start sending incorrect signals to the ECU. Misreading the correct engine temperature, which affects mileage and performance. Couple pics of the sensor. Trying to figure out who makes it. It's not Denso. The mark looks like Tie or Tiej. I don't know.
Do I need to coat the threads with any kind of additional sealant? Any other suggestions?
Do I need to coat the threads with any kind of additional sealant? Any other suggestions?
I think the part # listed (89422-30030) is for 2004 to 2006 LS's. Can someone confirm?
Also, what was the final verdict with Teflon tape or anti-seize, etc, on the threads?
How much/little coolant seeped out of the hole?
Finally, does anyone have the torque spec when tightening?
Not sure what the torque spec is but nothing should be put on the threads. I just tightened until nice and tight based on how it was to remove the sensor. I believe that some part number actually is for all 6 years of the 430.
Last edited by Lavrishevo; Aug 30, 2015 at 07:52 AM.
