Error Code 25

[Toyotacelicagt4]

CEL went on the other day and when I check my error codes it says 25 which would be an excessivly lean AFR. All I can really think too check would be the oxygen sensor, which was very rusty( could this be the problem? ) and looking around for air leaks. Anybody else got any ideas for things to check, and how I would go about performing the tests, as my gas mileage has been real crap lately ( ~14mpg :( ) and could this be the cause of the poor gas mileage?

P.S: I only checked the sensor before the catalytic converter, Is there another after cat sensor on a 185 that i should be checking as well?

[GTForbes]

sounds like the sensor is gubbed, the one before the cat is the one that is important, IIRC the sensor post cat is just a temp sensor

[Toyotacelicagt4]

ya I checked the pre-cat sensor and it looked real rusty probly hasnt ever been changed and the cars at 108,000k. Any Idea where I could find a replacement for a 185 and how many wire design im looking for?

[GTForbes]

you'll need to see how many wires go into the one you've got. i used to have a great site where i got mine but i lost that two computers ago, been that long since i had to get one.

[Toyotacelicagt4]

Ya i suppose I will have to check this out this weekend as long as I match the # of wires and the make/model it should be compatible? And you don't happen to remember any brands to suggest do you?

[Toyotacelicagt4]

Found a good site for replacements alot cheaper than Toyota, big suprise. Its a single wire sensor in my car. looks like it was just twisted into a connection then taped.... Im hoping that the swap might be as simple as cutting or removing the wire from the origonal sensor then crimping the new one into place or will it be a pain like everything else in these compact engines?

[GTForbes]

thats all i done to change mine and it worked a treat, whats the site?

EDIT: the one i used was SAP motor parts

[dawesy]

might be worth putting a new connection on first (crimp on spade will be fine) as it could just be a poor connection

[Toyotacelicagt4]

Could mt atmospheric DV be the problem with economy also? Because I know that these can cause the car to run rich on shifts and when you are on/off the throttle but would it be this noticable? Currenlty getting about 21.5MPG (30/70-city/highway)