Mazda3 Check engine light, error codes…First timer

[martdim]

hello all, first timer here ... got these codes with the ForScan software, wondering if anyone has any experience? or is your advice to head directly to the shop

Also, is it worth subscribing to alldata.com or eautorepair.net to try to diagnose the issues myself? I have no issue tinkering with my car but of course I don't have any specialized tools that dealers/shops might have

===TCM DTC P0841:00-2C===
Code: P0841 - Transmission Fluid Pressure Sensor/Switch 'A' Circuit Range/Performance

Status (-2C):
- DTC Maturing - Intermittent at Time of Request
- Malfunction Indicator Lamp is Off for this DTC

Module: Transmission Control Module

Freeze Frame #1:
-DTC: --- - DTC That Caused Required Snapshot Data Storage
-LOAD: 34.51 % - Calculated Load Value
-ECT: 68 °C - Engine coolant temperature
-RPM: 707 1/min - Engine Revolutions Per Minute
-VSS: 3.0 km/h - Vehicle Speed
-SPARKADV: 13.50 ° - Spark Advance
-IAT: 36 °C - Intake Air Temperature
-TP: 14.90 % - Throttle Position
-RUNTM: 230 s - Time Since Engine Start
-WARM_UPS: 254 - Number Of Warm-ups Since DTCs Cleared
-CLR_DIST: 1836.0 km - Distance since diagnostic trouble codes cleared
-VPWR: 13.85 V - Control Module Voltage
-APP_D: 8.24 % - Accelerator Pedal Position D
===END TCM DTC P0841:00-2C===

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===PCM DTC P0442:00-AC===
Code: P0442 - EVAP System Leak Detected (small leak)

Status (-AC):
- DTC Maturing - Intermittent at Time of Request
- Malfunction Indicator Lamp is On for this DTC

Module: Powertrain Control Module

Freeze Frame #1:
-DTC: --- - DTC That Caused Required Snapshot Data Storage
-FUELSYS: Closed Loop - Fuel System Status (Open/Closed Loop)
-LOAD: 33.33 % - Calculated Load Value
-ECT: 89 °C - Engine coolant temperature
-SHRTFT1: 0.00 % - Short term fuel trim 1
-LONGFT1: -2.34 % - Long term fuel trim 1
-MAP: 43.0 kPa - Manifold absolute pressure sensor
-RPM: 685 1/min - Engine Revolutions Per Minute
-VSS: 0.0 km/h - Vehicle Speed
-SPARKADV: 11.50 ° - Spark Advance
-IAT: 28 °C - Intake Air Temperature
-MAF: 4.40 g/s - Mass Air Flow
-TP: 14.51 % - Throttle Position
-RUNTM: 1171 s - Time Since Engine Start
-EGR_PCT: 0.00 % - Commanded EGR
-EVAP_PCT: 7.06 % - Commanded Evaporative Purge
-FLI: 42.35 % - Fuel Level
-CLR_DIST: 4173.0 km - Distance since diagnostic trouble codes cleared
-FTP: 0.1 kPa - Fuel Tank Pressure Transducer
-BARO: 100.0 kPa - Barometric pressure
-CATEMP11: 574 °C - Catalyst Temperature Bank 1, Sensor 1
-VPWR: 13.94 V - Control Module Voltage
-LOAD_ABS: 26.27 % - Absolute Load Value
-EQRAT11_CMD: 14.586 :1 - Commanded Equivalence Ratio (Air to Fuel Mixture) Bank 1
-TP_REL: 5.49 % - Relative Throttle Position
-AAT: 26 °C - Ambient Air Temperature
-TP_B: 14.51 % - Throttle Position Sensor 2
-APP_D: 7.84 % - Accelerator Pedal Position D
-APP_E: 8.24 % - Accelerator Pedal Position E
-TAC_PCT: 6.27 % - Commanded Throttle Actuator Control
-SHRTFT12: 0.00 % - Short Term Fuel Trim (Bank 1, Sensor 2)
-LONGFT12: 0.00 % - Long Term Fuel Trim (Bank 1, Sensor 2)
-ECT2_SUP: Yes - Engine Coolant Temperature Sensor 1 supported
-ECT1_SUP: Yes - Engine Coolant Temperature Sensor 1 supported
-ECT1: 89 °C - Engine Coolant Temperature Sensor 1
-ECT2: 46 °C - Engine Coolant Temperature Sensor 2
-ECT2: 46 °C - Engine Coolant Temperature 2 - Voltage
===END PCM DTC P0442:00-AC===

-----------------------------------------------------------------------------------------------------------------------

===OBDII DTC P0442-C===
Code: P0442 - EVAP System Leak Detected (small leak)

Status (-43):
- Confirmed - malfunction is confirmed

Module: On Board Diagnostic II

===END OBDII DTC P0442-C===

 

[edmaz]

Always a good thing to include your vehicle year/model, mileage, and any recent work done. You also didn't mention anything you've done so far for these issues, so I'll ask if you've checked the gas cap.

 

[martdim]

yeah, sorry about that
2011 Mazda 3 Sport GS 2.5, HB, 150k km. Most recent work was end of May, one of the ball joints was replaced.
I did lots of reading on these; found useful info here and there. Like on the "EVAP System Leak": cleaned the gas cap with WD40 but I don't see any problems with the cap really. Watched a video where a shop used a smoke machine to check the purge valve, etc.
Someone else said they replaced the transmission sensor, well I guess I can try that but is it the sensor or is it what it senses?

Thanks, apprecieate your help

 

[edmaz]

Yes, a smoke machine, along with one or two pressure/vacuum gauges, is the typical and preferred way to diagnose an EVAP leak. And for most DIYers, that would mean a trip to a shop that has one and knows how to use it effectively.

However, before deciding about that, I believe it would be worth your while to examine the purge valve, and then run a simple electrical function test on it. I'd always do that (and also the vent valve) automatically myself for most any EVAP code, but in your case the snapshot data that you posted has a smoking gun with that EVAP_PCT of 7.06%. That PID should normally always be either 0 or 100%, so that odd value could very well be an indication that the purge valve is stuck slightly open. So I recommend taking a look at it first to see if it's stuck partially open by simply trying to blow air through it. No aire should come out the other port if it's completely closed, as this NC valve should be with no power applied.

And in one of those curious coincidences, I actually replaced the transmission pressure sensor on my daughter's 2011 M3 (2.0L in hers), to resolve that exact same P0841 code. There's some testing that can be done on that sensor, if you're interested in doing that. Or if you don't want to bother testing, you can just hang a new one of these fairly inexpensive parts on - fairly easy access, located on the tranny case, down by the ATF cooler.