Smog Failed/Check Engine Light HELP!

[Ghostface900]

The time was up for me to renew my tags on my 1997 Ford Explorer,but in order for me to get my stickers I needed a smog.I went and got one and if failed. the test said it was my bank 1 and bank 2 o2 sensors only.So I went out and bought four instead of two,just to have them all brand new.Upon completion of the o2 sensor change.I reset the check engine light with the http://www.amazon.com/OBDII-Engine-...s=automotive&ie=UTF8&qid=1302774135&sr=1-3,So then I started the truck and the check engine light stayed off for a good 2-3mins and then low and behold it came back on,ran the scanner and it says its my o2 bank 1 sensor heater,o2 bank 2 sensor heater ect... (meaning it says it's all four of them this time with my scanner.)So I went back and exchange them for four new ones,replaced them and even replaced my EGR valve,and yet the same thing happens over and over again,any advice would be greatly appreciated
1997 Ford Explorer 4.0L V6 2wd.

 

[jremington59]

You need to tell us what code came up.

 

[1998Exp]

Replacing oxygen sensors when there is a problem is like replacing the thermometer when you have fever. The sensors rarely fail. You need to find and correct the root cause of the excessive emissions problem. As someone already stated, providing the detailed numeric codes may help with more detailed advice.

The time was up for me to renew my tags on my 1997 Ford Explorer,but in order for me to get my stickers I needed a smog.I went and got one and if failed. the test said it was my bank 1 and bank 2 o2 sensors only.So I went out and bought four instead of two,just to have them all brand new.Upon completion of the o2 sensor change.I reset the check engine light with the http://www.amazon.com/OBDII-Engine-...s=automotive&ie=UTF8&qid=1302774135&sr=1-3,So then I started the truck and the check engine light stayed off for a good 2-3mins and then low and behold it came back on,ran the scanner and it says its my o2 bank 1 sensor heater,o2 bank 2 sensor heater ect... (meaning it says it's all four of them this time with my scanner.)So I went back and exchange them for four new ones,replaced them and even replaced my EGR valve,and yet the same thing happens over and over again,any advice would be greatly appreciated
1997 Ford Explorer 4.0L V6 2wd.

 

[2000StreetRod]

O2 sensor heater codes

The PCM tests the O2 sensor heater paths for an appropriate resistance/voltage. The heaters rarely fail. If you have multiple heater failures then you probably have shorted wires, incorrect wiring or bad electrical connections. Did you purchase O2 sensors with installed connectors or just pigtails? Are you sure the connectors are firmly pressed together and latched?