sithjedi33

Hi all! Great forum. I have a 1991 LS400 with about 90k miles on it. Traction and check engine lights were on, so I took it into the dealer. They said 2 oxygen sensors ($700) and the throttle position ($300) need to be replaced.

My question is, are these things that need to be replaced immediately? How dangerous is this type of problem? I thought oxygen sensors are primarily for fuel efficiency and emissions, but the service guy says that the cats can get blocked and heat up. He said the throttle position can cause the car to stall, although I haven't noticed any problems while driving.

Any insight would be greatly appreciated. Thanks, and Merry Christmas!

SRK

Ask them what codes they found. Each of the four O2 sensors has a specific code for it, and the throttle position sensor has one too. If only one O2 is bad, just replace the one. The pre-cat O2's check the fuel trim, and are an important part of the engine management system. If one of them failed, you would have noticed a very smelly exhaust. The post-cat O2's check the functioning of the cats, and do not affect the fuel trim.

VQT

I paid about $450 for a pair of O2 sensor for my 93 SC400. Call Gordon from Carson Toyota (Los Angele) and get the correct price (mention you're a forum member he might get you at cheaper price. I guesw the remaining of the $700 is for labor... $250 for 30 min. of work is no bad...

Need to have the correct error code before uy thes expensive parts... buy a shop manual and fix the car yourself . The books cost less than $200. I rthe pay for the book and learn to fix the car instead of paying $250 for the dealer to change my oxygen sensors... an easy job anywa you look at...

5ofakind

The best money you will ever spend on your Lexus will be for a set of factory repair manuals for your specific year.

O2 sensors & throttle position sensor are easy fixes.

Dealer's labor to replace these seems high.

Replace yourself.

Jeff

sithjedi33

Thanks guys for the great responses.

Lvangundy

$300 for the TPS replacement is pretty steep.

The part is about $100, labor should be 30 minutes.