Hey guys,
I hope this is the right place to discuss this and I apologize if its not. Its been a really long time since I was last on this site. Anyways, to the point, a couple of months ago my check engine light came on in my 8 and I took it to the dealership. Of course they said it was the rear oxygen sensor behind the cat. Long story short, I have emissions coming up in a few weeks so I ordered the sensor from mazdapartsonline and installed it. Took it for a ride today and the check engine light is still on. Any suggestions, any way to turn that damn light off or am I going to have to bite the bullet and pay $40 just for mazda to hook my car up and tell me what is going on? Thanks.

 

Reset the ECU.....remove -ve battery cable and step on brake pedal for 30 sec or so....reconnect
Turn key on....tap brake pedal 20+ times til oil pressure gauge sweeps..turn key off than back on...turn steering wheel lock to lock....turn off key

Turn on...restart...should be good

 

The ECU monitors the sensors over a few 'drive cycles' which are one complete trip (startup, warm fully, steady speed and cool down) each, so if it was the sensor and that is the only problem, the light might stay on for two or three days.

So you could just give it a while....

For $80 or so, you could buy a scanner that reads codes (Autozone, PepBoys etc) they usually have a 'reset' button. The scanner may tell you that it's the cat that's faulty, not the sensor (very likely) - which is actually good news since Mazda is liable for the cat for 80k miles, so you get a new one, free.

Good luck wit dem 'missions!

S

 

hey guys. I appreciate all the help and it looks like all it needed was a little bit of time to cycle and reset. Thanks for that ECU reset trick though, that could come in handy sometime!

 

could always go to autozone or the like and have it read and erased for FREE!!!!!

or disconnect the battery for a few minutes