LSDoc

Ara,
I'm having CEL issues similar to yours. Thanks for sharing, and I'm sorry to hear that you've gone through such a harrowing experience.
That's one more DIY 'adventure' that I'll be crossing off my list...

LS430inDE.

No problem Doc. I spoke with my mech about an hour ago. He told me he spent 3 hours replacing both pre-cat sensors today. He said he took a tap to both threads and clean them up to be able to spin the new sensors into place.

Apparently, the factory anti-seize on my 2005, had been vaporized and transformed to rust, after 133k+ miles.

Envious of the other members who were able to this work themselves.

Maybe if we took the suggestions of Tom & Lav and did this sensor replacement as part of a routinely scheduled interval (every 50-75k miles?), we might not have this problem of rusted in place. I have a northeast vehicle, though.

My guy said my bill was only $75 though. I greased his palm yesterday with alcohol and gas $$$ for his boat. I want to ensure I don't wear out my welcome!

Arcturus

Good on you for getting in there and getting your hands dirty. Did the CEL go off? Even though it seemed like a rotten job, you just saved yourself the pleasure of getting bent over at the dealership. I sympathize with you in that every car repair job I do nothing goes as planned. You can see my thread on "wheel hub stuck to spindle" where I spent several hours trying to yank a pesky wheel hub off to replace the ABS sensor. Most people said it would only few taps with a hammer. For me, after several hours trying various methods, I had to take the whole knuckle off to get shop to press it out.

Lavrishevo

iTrader: (1)

How is the car running?

LS430inDE.

Great question Lav. I don't know yet! LOL!

He never did make it back up my way for business, so he never 'delivered' it, and he still has the LS.

He did changeout BOTH pre-cat sensors and did say the CEL is now out. However, we know it's meaningless that it's out right now. Several full hot/full cold cycles over several days hopefully will produce no lights though.

My gf and I will be heading south to his place either Sat or Sun (week from today) to pick it up.

I'm very curious to see what my 'tank avg' fuel economy will be after doing this work.

Rest assured, I'll post it here!

Lavrishevo

iTrader: (1)

Two weeks without your LS!

Inconceivable!

LS430inDE.

So I just got home from picking up the LS from my mech. He replaced both pre-cat O2 sensors. He had to re-tap both of them.

As I drove my F150 home, my GF followed me. it was about 45min drive of 50-65mph, and about 10m of stop/go traffic on i-95.

Before we left to come home, I made my GF put the dash display to show TANK AVG MPG.

When we departed my mech's house, TANK AVG MPG showed 18.1.

An hour (about 50miles) later, we pulled into my driveway, and it shows 20.3!

I was hoping to get slightly more MPG with the O2 changouts, but now I'm curious to see how much FURTHER the increase in my MPG continues. I'll post a week from now and let you know if it stays around 20.3 or if it continues to go up.

In the meantime, I'm going to study the thread relating to the coolant temp sensor DIY. I'm so jealous of LAV and his Prius-like fuel economy!

(Not sure how the LS is "driving". my GF drove it the entire ride home). Stay tuned!....

Lavrishevo

iTrader: (1)

I just drove from Princeton to Newark and got 30.2 on 95 section for 19 miles. Part of the reason for great mileage is because I have a UL. I pretty much set cruise to 70mph. This gives me ideal mileage. I would no be surprised if yours jumps up to 25-27. Try setting the cruise at 70mph, reset the average, and see what she will do.

jimbosr1

when i lived in baltimore the only time of the year you could use the cruise control on I95 was thanksgiving day and christmas day.traffic sucked.

LS430inDE.

what, if I can ask, brought you to Newark? We were there this morning moving my GF's daughter into Univ of Delaware today!

LS430inDE.

Question for you guys who have changed your O2 sensors, or even for those of you who haven't changed them. How quickly or how fast do you see your fuel economy TANK AVG MPG go DOWN while at a red traffic light or going up a hill, etc?

I ask because a couple days ago I had my first fill-up of the tank after both O2 sensors were changed. The TANK AVG MPG resets itself. I understand that and am aware of that.

The following days after the fill-up, I literally witness my MPG tick down .1, then another .1, then another .1 while sitting at a red traffic light. I mean, literally almost .5 MPG decrease right before my eyes while sitting at the traffic light for maybe 2 minutes? I never had this phenomenon before.

While it does go back UP rather quickly, which I also didn't experience frequently, I'm just wondering if you guys see this .1 downtick and .1 downtick and .1 downtick at a red light?

For a while (too long, lol) and before I came to my senses, I was thinking I had a LEAK in my fuel tank..lol

Before both sensors being changed out, I almost always viewed between 18-20 TANK AVG. Never did I ever (remember) seeing it down-tick before my eyes. Maybe I'm hyper-obsessed with viewing the TANK AVG since the O2 changeout?...

FYI.....my tank currently is over 7/8 full since the fill-up

volson

Its just math. Once there are more data points it will be harder to move the average.

LS430inDE.

I hear you, but before the sensors were changed out, I never remembered seeing my TANK AVG MPG tick down so quickly merely sitting at a red traffic light.

Today I drove the LS to Dover AFB and back. It's 1 hour down and 1 hour back trip, and 98% of the drive is highway cruising between 60-75mph.

Upon arrival back home this afternoon, my TANK AVG MPG is showing 23.8 (and was still ticking up!!!) Personally speaking, with my LS, that's an awesome number! I don't think I've ever seen over 24, but I'm willing to bet if I drove only highway for the next 60 miles it would be almost 25!

I'm amazed.

Lav, I'm going to catch up to your MPG.

Arcturus

You will notice a SIGNIFICANT difference in fuel mileage on the highway vs city driving with this car. It seems like I can get over 800kms on a full tank on the highway if I drive at a constant speed vs 550-650kms in the city.

Sharondel

Hi - I got the same message on my 2007 Lexus GS 350 last week. I was driving locally on the street, no more than 20 mph and the computer said Check VSC, the VSC indicator as well as the check engine and exclamation mark icon lit up. The car to me seemed to be driving just fine. But I too panicked and took it into the dealership to check what it meant. I was hoping it had something to do with a recent recall they completed 2 weeks prior on my car. But no... turns out it is a transmission error. The solenoid cylinder is in the stuck position and the transmission is not performing well. Ughhhhh. Lexus quoted me $4950 tax included for a re-manufactured transmission. I took it to my mechanic who only uses lexus parts and that I trust.. and am paying not much less.. $4700 but with a 2 1/2 yr warranty. I have about 120K miles on the car. Took it in Monday .... hoping to pick it up later today (Thursday). I absolutely love my Lexus but the maintenance / repairs are so costly.