Hi,

after the previous oil change, my engine light came on and stayed on for awhile. After a couple of months, I did a drive to Brisbane . The engine light was on and off during the drive to and from. After returning, I Drive my car to town and on the way it started losing power. It was surging a little bit and ended up from 100 down to 20 km an hour. I pulled over and stop the car. I had someone to come and they disconnected the battery and turn lights on, then reconnected battery, turned lights off and traction control light came on when restarting the car. I drove the car home with absolutely no issues which is about a 20 minute drive. I have use the scan tool and have had codes come up which I have attached images. They flow sensor is working correctly as we unplugged it while in ignition running and the car switched off. Can someone please help as it seems to be a few codes are in error and now the engine light comes on and if the engine light goes off the traction light comes on.


codes CAT HCAT EVAP AIR O2S HRT EGE ON IN MAZDA CX7

 

You need to take it to shop . As a DIY there are to many things first that were done wrong , ( disconnecting the battery) before the original issues were diagnosed now some by disconnecting the battery it may have added to the collection of issues.

It’s nice that you retrieved some info but like many of you don’t have training in diagnostics trouble shooting you are likely to create or delay the correction of your issues.

If you do what I recommend make sure the service shop has an actual certified Automotive technician . Other wise you are likely going to pay for a mechanic guessing at your expense .$$$

 

okay, thank you for your reply I appreciate it. Yes, that was going to be the next step, but I just was hoping it was possibly a sensor issue. Unfortunately we did have to do that to drive the car home as I wasn’t prepared to leave it on the side of the road where vehicles are stripped of tyres very quickly. I took the car for a drive today and the traction light stayed on but car drove perfectly. Once I stopped and then restarted the car to come back home all lights had disappeared from the dash completely. I am just in between jobs so was hoping to avoid big costs. Thank you for the tip on the certified order automotive technician. I will definitely look for one

 

Just because the “Dash” engine check light is off does not mean the problem is corrected. Also your pictures shows a generic DTC and suggested causes. Not all the causes. Pictures 3 clearly show you have more going on then your post description and the pictures. Also some problems are unrelated to some others.

Again it is nice to have a scanner but IMHO without getting training they are more a pia when used to solve issues the wrong method or correct way.

I would not drive much based on what you posted , doing so can create more problems adding to the cost to correct.

I also don’t recommend that you show what ever service shop you go to your findings . We really don’t need to be shown how to find issues and some service shops tend to add to the service repair replacing unnecessary parts based on customer info using a scan gauge . Let the shop find your problem and always ask for any and all parts replaced returned to you. This insures somewhat that they did the service correct .



i also highly recommend in the future no matter what you may read or get told….don’t discount your battery in your Mazda hope to correct problems. It does not work that way and technically from about 2002 to present never really did. MYTH at its best .

 

Ok great information
thankyou I am searching now for a certified automotive mechanic. Will I still be able to diagnose the issues, even though the codes are cleared from the dash?

 

All that happened is the ECU turned off your dash check engine light. The DTC if your scanner is capable to enter the permanent DTC file to see any active DTC that have not yet been corrected. The I/M monitor after several engine cycles will set to state of ready emissions only when all the DTC have been corrected. The I/M Monitors are semi tamper resistant so all you can do is re-set them after the problems are resolved and they will all return to Green which means all emissions are no properly working. 3rd Picture of yours.

A drive cycle is a complete start and run to operating temperature after the engine has completely cooled down. When all problems are correct it can take 1-4 engine cycles to set all ECU perimeters back to normal. As long as you don’t continue to reset DTC I.e. check engine light, in the the ECU.


btw in picture 3 it shows you have 3 DTC active not just one as in picture 1 .
And you are confusing emission system readiness with a DTC.


thats it for me it’s 11 pm and I have work doing this in the real world tomorrow… lol oh and get paid .. lol 😂