The spark plugs have been replaced. The bogging is gone!!!!!! The check engine light remained on, and a friend of mine told me awhile back that if you disconnect the battery the light will turn off, so I decided to do this and the light is no longer on. Now is it possible that the cylinder misfire caused the others to read improperly? or may I still have a defective cat or O2 sensor?

 

Engine missfiring due to a bad or worn spark plug will not cause the IAT circuit fault code. Engine missfire could well have caused an early demise of the front catalytic converter but only time will tell that. Now that you have the CEL off then just go ahead and drive as you normally would and see if the CEL returns. A hard fault in theIAT sensor circuit should show up fairly quickly. The converter efficiency could take weeks or months to reset if it ever does. Here is to hoping that the light stays off and all system checks come up good.

 

Once again thntk you for all your help!!! One more question for ya. In the past with others cars I have owned I have replaced the wires with the plugs. AutoZone quoted 2 wires to me at $30. The Mazda dealer, on the other hand, quoted then to me each sold seperatly at an average of $45 a piece (and that there were 4 to buy). So I decided to called Autozone back and they explained to me that the wires themselves should be replaced (good idea anyways) but the 2 boots under the "coil packs" are fine until the coil packs go out.

Do you recommend changing the wires at all? Just the 2? All?

 

Dealer obviously does not know what you are driving or what they are doing or would not have quoted you for four wires at that price.
Replacing the2 plug wires that supply spark to the #1 and #3 cylinders is up to you and your wallet. It is certainly a good idea to get a new set of wires if you are getting up there in the mileage. They are carrying quite a load with that kind of voltage and do tend to break down over time.Have not really had that many problems with either the coils or wires going out on the 2.0l engine. The only problem I have had so far was in using aftermarket. Used aftermarket sets twice when wires were needed and we did not have OE in stock. Neither set made it longer than a month. You may have different luck with yours. Retail for the OE are more than Autozone at MSRP of $27.17 and $25.45. If you order from www.onlinemazdaparts.com you can get both for about $43.00. OE part number for long plug wire is fp85-18-140a. Short wire is fp86-18-140a.