QuestionQUESTION: My Check engine light has been on for quite awhile. The car continues to run
great. However, I got a free scan from the local auto parts store and he said it
was one of the O@ sensors. The diagnostic refered to bank 1 and being too lean.
How many O2 sensors are there on a 99 Contour, where are they, and why does my
car run well if one is bad? Is there a way to fix without replacing? I have a 2.5L V6 Duratec engine with 130K miles. 5SP manual.
ANSWER: Oxygen sensors do not generally effect engine performance as a standard. They more effect fuel economy,which is just not noticeable. Your Contour as 4 oxygen sensors, for the record.It has two catalytic converters each with one sensor before and after the catalytic converter. Generally the sensor before heats the exhaust up 100 degrees to enable the catalyst. The second sensor located behind the converter simply reads and registers if the sensor before and converters are working properly.
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QUESTION: A mechanic suggested that I may be able to fix the siuation by running a few tanks of a higher grade fuel and using Lucas fuel injector cleaner. Any thoughts on this?
AnswerBoth very good recommendations, but not a solution. The first time I used that "tune up in a bottle," I noticed a performance upgrade immediately. Unlike most other injector cleaner, Lucas is not "refined kerosene." It is more like oil, and lubricates your rings, seals, and etc. Also, the fuel pumps lubrication system is the fuel itself, and it does help that. If it is a money issue, I have bad news. It is a highly recommended idea to replace all sensors, in each effected exhaust pipe. Basically, any pipe with a problem, is exposed to the same conditions that eventually took down the sensor that you know is bad. Keep an eye n any catalytic converters on said pipes. Prolonged exposure too a rich burning combustion does cause catalytic converter failure. The converter is comprised of precious metals that is very recyclable, there is money in that damaged converter. That is the good news if you decide to replace the converter as well. Get the OEM parts, or Walker if you decide to go aftermarket.
