Ok, so this morning I took out the new Denso O2 sensor that I had installed a few months ago, which after a little research found that it was a O2 sensor for a California emissions pickup. After pulling it, I inspected it and compared it to my factory O2 sensor. There was a considerable difference in the actual sensor portion which contacts the exhaust. The factory O2 sensor had a white tint to it and looked similar to what a properly running 22RE should look like. The Cali Denso O2 that I pulled out was covered in a considerable layer of black suet, like it was causing the engine to run very rich, which I am pretty sure is the main reason for the slacking fuel mileage. So for now, I reinstalled the factory O2 sensor and will monitor it to see if there is any improvement in mileage.
This brings me to my next question. I came across a statement in one of the topics in this formum stating that Toyota will give you a new O2 sensor free of charge once your vehicle has passed the 80000 mile mark. So this morning I checked my owners manual just to see for myself and sure enough there it was on page 157 of the 1994 Owners Manual. And I quote "Oxygen Sensor-Replace the oxygen sensor when scheduled. Your Toyota dealer will make this replacement (parts and labor) at no cost to you". So has anyone had any experience with this, please pass along any information that my be relevant. For example, do I need to be the origanal owner, is this only a warranty related thing, ...etc.
Any comments or advice would be most appreciated.
Also VE3NLP I have doses my fuel with a couple of servings of the Lucas fuel treatment and while I am sure it has helped the intake system, it did not do anything noticeable to the fuel mileage. But thanks for the suggestion.
