Replaced My Ls430 Front Oxygen Sensors Today

[Bon]

My car: 2001 LS430 with 56,000 miles

My symptoms: Slightly rough idle; some smell to the exhaust; approx. 25% decrease in fuel mileage :cries: ; no check engine lights showing.

I suspected a front oxygen sensor had gone bad so I ordered two generic Walker units for about $35 each to replace both while my hands are dirty. After removing a plastic shoud around the transmission the front two oxygen sensors are easy to see. You MUST have an oxygen sensor socket tool, that can be purchased for around $10, to extract the sensors as they are surrounded by a heat shield that denys all other means. The hardest part of the job is disconnecting the sensor plugs from their other half. The locking tabs are placed in a position that makes them impossible to see and just about impossible to press to remove. The right side is difficult but at least I could get a finger into position to press while pulling on the connector and it came off with some effort. The left side was much tougher and required a small screwdriver to wedge into the locking mechanism (while pulling) to release the connector. Whew - What a pain!

Since I bought generic 4-wire replacements I cut and spliced, by soldering, the original connectors to the new sensors. Took some time but I'd do it the same way again. Just remember that the right and left wire lengths are different. The generics come with crimp splices but since I've read about poor crimp splices causing problems I chose to solder the wires.

After installing the sensors I'm pleased to say that my great gas mileage is back and the idle is perfect and without any exhaust smell.

Total expense $70 (2 sensors) + $10 (tool) + $10 (shipping) = $90

Lesson learned: Watch your gas mileage as this might be the best way to find a faulty oxygen sensor. With gas prices as they are today, you'll get your money back within a couple of months driving time.