Where did you get the OX sensor? And if I may ask, what did you pay for it? I have a reason for asking. You do realize don't you that the 2 front sensors (1 on each bank) are A/F (air fuel) ratio sensors, not oxygen sensors? Many places will sell you the universal oxygen sensors and swear that they are the right ones, BUT THEY ARE NOT. If they are oxy. sensors and not A/F ratio sensors, they are the wrong thing. The problem is A/F ratio sensors are routinely called Oxygen sensors and they are VERY MUCH different! If it is the correct Denso sensor, it may be universal without the plug and work. Give us some details and we can tell you whether to waste your time figuring out the colors.
Ordered this thru US Autoparts Network. Part # USOS-4000. Paid $48.00.
