Need some help please......I just got this car a week ago and now the engine light is on. I got the code read and it gave a catalytic effieciency or ineffeciency code (pardon my ignorance on exact terminology). I was told it could be either a bad catalytic converter or a bad O2 sensor and this could be figured our by running a full diagnostic. Does this sound right and can you give any further guidance on this issue? Thanks in advance.

 

Was it a P0420 that was the cause of CEL? P0420 is Bank 1 cat efficiency below limit. Rarely does a faulty oxygen sensor cause a cat efficiency code as the O2 sensors have their own separate codes for different faults. Yours has very few as it is a very early OBDII system and Mazda was not quite up to speed on coding yet. A full diagnostic. Not really. Basically the output voltages of the front and rear Oxygen sensors need to be monitored to determine the condition of the converter by measuring the number of inversion ratios each sensor produces in a fixed amount of time with a fully warmed up CAT. Does that help?

 

Welcome to the forum a fellow ham! QSL?

 

Yes, this was the code. Sorry for the previous poor explanation. It has since been tested and I am told that the Catalytic converter is shot? Does this sound like what would cause this code?

 

Excellent!! Always glad to meet another Hammy!! I am in the Dallas, Texas area!! Might I ask your callsign? QSL?

 

Yes it would cause that code. bkey should be almost close enough to where you are that you should be hollar out the window at him.

 

The callsign is K5BRK. I live NW of the San Antonio area. As soon as I saw your user ID I suspected a callsign then looked it up to find out for sure. Welcome to the forum!

 

Thank you and it is always great to make contact with other Ham's!! Hey, Now this goofy little Protege is running HOT [:@]!! What is the first thing that you would suggest I check. It runs fine without the AC on, but still a little hot. Then with the AC on is gets real hot real fast. Is it a thermostat or something like that? I'm don't know alot about cars, but am mechanically inclined if I know what it is I am suppose to doing and looking at? Suggestions?

 

Also, sorry for some of the typos on the last reply and question that I asked. I'm a lot smarter than that would lead you to believe. I was just in a hurry with my typing!!

 

A thermostat that is not opening all the way is a possibility. Another thing to consider is the radiator. They are not that big in this car and leave very little room for error in case they start getting clogged. I have 150K on my car so I just bought a new one. These Tx heatwaves are pretty fierce so a new radiator is cheap insurance to me. It was only $120 new with a lifetime warranty and delivered Fedex next day.

BTW, if you need to edit your spelling, there is an "edit" icon above your post just in case.