Another P2178 intermittent

A

Alidins

Greenie N00B Member
ENGINE/DRIVABILITY
Stock and running decent enough

Year/Make/Model: 2007 mazdaspeed6

Mileage: 155,000km / 96,000miles

Location: Canada,AB

Concern: intermittent can’t reproduce it rich condition

DTC's: Raw: 07E805 returned 2178

Modifications: overspeed injection seals, gas cap, catalytic converter

ECU/Tuning Software: stock mazda did some recent software/firmware update

Tuner: stock

Is the concern intermittent? Yes

Can you duplicate the concern? Randomly before i can go through a full tank of gas

Recent Repairs: all posted below this
had the issue now around 20,000km or 12,000 miles was plugging randomly hoping to fix the issue with a big tune up ill post raw data from my reader from the second it was tossed in the correct order from when i had proper data readings



Absolute Barometric Pressure: 88 kPa

Absolute load value: 63.14 %

Absolute throttle position B: 23.92 %

Accelerator pedal position D: 31.37 %

Accelerator pedal position E: 20.78 %

Ambient air temperature: - 1 C

Calculated engine load: 36.5 %

Catalyst Temperature: Bank 1, Sensor 1: 821.6 C

Commanded EGR: 63.1 %

Commanded evaporative purge: 0.0 %

Commanded throttle actuator: 17.65 %

Control module voltage: 14.128 V

Distance traveled since codes cleared: 93 km

Engine RPM: 2794.25 rpm

Engine coolant temperature: 96 C

Fuel Rail Gauge Pressure (diesel, or gasoline direct injection):

11530 ??

Fuel Tank Level Input: 74.1 %

Fuel system status: Closed loop, using oxygen sensor feedback to determine fuel mix

Fuel-Air commanded equivalence ratio: 12861.57

Intake air temperature: 1 C

Intake manifold absolute pressure: 63 kPa

Long term fuel trim-Bank 1: -20.31 %

MAF air flow rate: 40.45 g/s

Raw: 07E805 returned 2178

Relative throttle position: 14.12 %

Run time since engine start: 696 s

Short term fuel trim-Bank 1: -4.69 %

Throttle position: 23.5 %

Timing advance: 32.5 degrees

Vehicle speed: 118 km/h

Warm-ups since codes cleared: 1


@145k mechanics did all this for no fix private shop not sure on the brand name or the quality they used but the problem was there before and it’s still there now didn’t make anything better or worse

-New upper oxygen sensor

-New lower oxygen sensor

-New mas airflow sensor

-New spark plugs

-New coil packs


Absolute Barometric Pressure: 92 kPa

Absolute load value: 80.39 %

Absolute throttle position B: 25.1 %

Accelerator pedal position D: 41.57 %

Accelerator pedal position E: 30.2 %

Ambient air temperature: -26 C

Calculated engine load: 40.0 %

Catalyst Temperature: Bank 1, Sensor 1: 826.7 C

Commanded EGR: 0.0 %

Commanded evaporative purge: 0.0 %

Commanded throttle actuator: 18.82 %

Control module voltage: 14.611 V

Distance traveled since codes cleared: 14 km

Engine RPM: 2958.5 rpm

Engine coolant temperature: 71 C

Fuel Rail Gauge Pressure (diesel, or gasoline direct injection):

11460 kPa

Fuel Tank Level Input: 27.5 %

Fuel system status: Closed loop, using oxygen sensor feedback to determine fuel mix

Fuel-Air commanded equivalence ratio: 12835.69

Intake air temperature: -26 C

Intake manifold absolute pressure: 69 kPa

Long term fuel trim-Bank 1: -20.31 %

MAF air flow rate: 56.71 g/s

Raw: 07E805 returned 2178

Relative throttle position: 15.29 %

Run time since engine start: 493 s

Short term fuel trim-Bank 1: -5.47 %

Throttle position: 24.7 %

Timing advance: 15.5 degrees

Vehicle speed: 77 km/h

Warm-ups since codes cleared: 1

the second data sheet posted above may have been before or after they worked on the car, can’t recall


@156k did my self

-added block heater

-New Gas cap
Aftermarket oem spec

-New Right rear shock absorber

-Clean EGR

-Cleaned throttle body

-Cleaned intake valves walnut blast

-Clean vtcs manifold valves

-New PCV valve

-Cleaned PCV housing

-New catalytic converter
Aftermarket oem spec

-New turbo

-New injectors

New seals overspeed

-Map sensor cleaned

-all new gaskets

-New power steering fluid ATF Castro

-New antifreeze FL 22

-New motor mount passenger side

-New trunk support hydraulic


156k brought to dealership to troubleshoot a vibration from a transmission mount I installed and removed after Mazda diagnosed the noise. They also found a issue.

-Mazda PCM update

-transmission flush my request gave them AMSOIL 75W-90 MANUAL TRANSMISSION & TRANSAXLE GEAR LUBE

-again another new lower oxygen sensor lower past the catalytic converter was reading 0v found during their diagnostic fee for the vibration


The light came back after half tank of gas

Absolute Barometric Pressure: 90 kPa

Absolute load value: 11.37 %

Absolute throttle position B: 14.12 %

Accelerator pedal position D: 32.16 %

Accelerator pedal position E: 21.18 %

Ambient air temperature: 16 C

Calculated engine load: 5.1 %

Catalyst Temperature: Bank 1, Sensor 1: 690.7 C

Commanded EGR: 0.0 %

Commanded evaporative purge: 0.0 %

Commanded throttle actuator: 5.49 %

Control module voltage: 13.568 V

Distance traveled since codes cleared: 248 km

Engine RPM: 2559.75 rpm

Engine coolant temperature: 89 C

Fuel Rail Gauge Pressure (diesel, or gasoline direct injection):

3120 kPa

Fuel Tank Level Input: 52.9 %

Fuel system status: Closed loop, using oxygen sensor feedback to determine fuel mix

Fuel-Air commanded equivalence ratio: 12842.35

Intake air temperature: 18 C

Intake manifold absolute pressure: 17 kPa

Long term fuel trim-Bank 1: -20.31 %

MAF air flow rate: 6.12 g/s

Raw: 07E805 returned 2178

Relative throttle position: 4.31 %

Run time since engine start: 406 s

Short term fuel trim-Bank 1: -7.81 %

Throttle position: 13.7 %

Timing advance: 38.0 degrees

Vehicle speed: 52 km/h

Warm-ups since codes cleared: 17


156k did my self

-Purge solenoid

still not fixed…

Absolute Barometric Pressure: 90 kPa

Absolute load value: 14.12 %

Absolute throttle position B: 15.29 %

Accelerator pedal position D: 32.94 %

Accelerator pedal position E: 21.96 %

Ambient air temperature: 11 C

Calculated engine load: 6.3 %

Catalyst Temperature: Bank 1, Sensor 1: 739.7 C

Commanded EGR: 0.0 %

Commanded evaporative purge: 0.0 %

Commanded throttle actuator: 7.45 %

Control module voltage: 14.012 V

Distance traveled since codes cleared: 387 km

Engine RPM: 2751.25 rpm

Engine coolant temperature: 73 C

Fuel Rail Gauge Pressure (diesel, or gasoline direct injection):

2930 kPa

Fuel Tank Level Input: 56.9 %

Fuel system status: Closed loop, using oxygen sensor feedback to determine fuel mix

Fuel-Air commanded equivalence ratio: 12877.25

Intake air temperature: 13 C

Intake manifold absolute pressure: 19 kPa

Long term fuel trim-Bank 1: -20.31 %

MAF air flow rate: 8.71 g/s

Raw: 07E805 returned 2178

Relative throttle position: 5.88 %

Run time since engine start: 34 s

Short term fuel trim-Bank 1: -15.63 %

Throttle position: 15.3 %

Timing advance: 39.5 degrees

Vehicle speed: 72 km/h

Warm-ups since codes cleared: 16


156k

-thinking of bring it back to mazda again at this point.


Correction: left wanting a new brain im a noob at mechanic troubleshooting but can follow good detailed instructions.


Thinking of letting mazda have a go it?? But ill gladly take advice and toss parts at it if it could be a possibility of a hand full of different parts or if this information is good for a specific part hell, yeah I’ll do it myself too.

I’m also gonna try the recommendation with the rich condition with the dipstick out watching the trims currently it’s on a pretty fresh oil change about 500k on the oil
 
Raider said:
Have you dine some reading in these threads?

Also, are you replacing sensors and solenoids with oem or aftermarket?

https://www.google.com/search?q=mazdaspeeds.org+p2178
Click to expand...

i’ve done some reading in some of the threads a lot of research on Google from threads and post in general. I have a list of parts I could start plugging away at I just don’t wanna introduce a lower quality product bring a problem sooner than later. I’ve also kept my stock parts. Except my master airflow sensor because it was done a little while ago cleaned up my garage and it was gone.

Aftermarket OEM spec
The most recent solenoid I replaced was
“Standard Motor Products” brand name tried selecting ones with higher reviews people marking them as favourites on rockauto.com

Although the lower oxygen sensor is from Mazda

my diagnostic tool could be labelling things differently as a “FIXD” scanner found on amazon. There’s definitely some limitations.
 
Yeah oem only. Won't fix the probkem with aftermarket.
 
Raider said:
Yeah oem only. Won't fix the probkem with aftermarket.
Click to expand...
Okay ill follow up with the mechanic shop that installed the upper oxygen sensor and source out if they got it from the dealer. I’m gonna go to Mazda and order a new mass airflow sensor and install that. That solenoid that I replaced didn’t seem to do anything so I’m gonna toss the mazda OEM one back in. Ill get back to you if the issue persist. I’m also not hesitant to buying a proper general code reader for vehicles that can give you guys better information.
 
have you done a boost leak test? also inspect your maf oring my car has been known to eat them. those LTFTs at -20 lead me to believe you have a massive leak range should be ideally +/-5 with +/-7 being acceptable.

when it comes to trims
Pre-turbo = + trims, air added or sucked in
turbo to Throttle body= - trims, air lost or pushed out
post throttle body= + trims, air added or sucked in

here's a thread on proven parts that arent from Mazda, some of them are the OEM such as NTK is the OEM for our oxygen sensors.

https://mazdaspeeds.org/index.php?threads/proven-parts-list-common-parts-that-dont-suck.4476/
 
The smoke test was fun and effective. I definitely recommend having a mirror handy. I successfully identified some leaks on the air intake side. Don’t use a Phillips screwdriver to tighten them by hand (as it rotates the hose clamp or will push the screwdriver up and out if not pressing hard enough mega trolling and miss leading thinking its tight enough ). it wasn’t sufficient. I had to use a 10mm socket with 6 ft-lbs of torque, which seemed tight enough to compress the rubber. I turned it a lot, so I hope it’s not too tight. I could not get my smoke machine to the recommended PSI level, which may indicate an extremely small leak. I still had an issue with my fuel trim levels, even after tightening everything down.


Next, I replaced the Mass Air Sensor (MAS) with the OEM Mazda part. The car hiccuped on the first start due to the memory of the long-term fuel trims. It bucked a bit initially but smoothed out as the short-term and long-term trims began to cancel each other out, staying within a 5% tolerance. It’s currently re-learning from a -20 long-term trim, which is decreasing as I drive, so I think it’s fixed. I’m seeing a lot of live data that stays within 5% more often than not now.


My long-term fuel trim is coming down to below -17% and continues to drop while cruising at regular RPMs around 2400 to 2900.


Anything under acceleration is 0% to -9% long terms and holding speeds outside of 2400 and 2900rpms is below 0% to -9% so still might be to early to say its fixed.


The video I linked really helped me understand fuel trims enough to read the data live while driving. Fingers crossed that no engine lights will come on, and I won’t experience any fuel cut issues or other problems. I’ve noticed a significant increase in performance and acceleration since replacing the MAS, so thank you for the link you shared for the purchase. I’ll definitely return if I encounter any future issues.


I plan to address the leak from the “Pivot Shaft Seal” in December, and I’ll replace the transmission mounts at the same time. They are currently on backorder from Mazda. The seal is sweating badly since the transmission fluid was just changed. I found some helpful information on that in the forums here as well. I’m going to keep it under 3k RPM full-time until then. I only did a few pulls after fixing the P2178 code, and I feel paranoid, like the transmission is squirting when I do that.

I hope this video helps newcomers understand fuel trims better.

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you can reset the tfiel trims by disconnecting the battery for 20mins. it's recommended to do so after you do the leak test (just disconnect during) that way you get a better snap shot if it worked.

glad the smoke check helped, with a turbo car you really want the boost leak test. how much pressure did you have with the smoke tester?
 
Still no light came back for that issue. Trims 90% of the time within 5%. Nowhere on my long term does it even go into double digits anymore.

It got to about .3 kg/cm2, but it said in the manual that if it gets to .5, there is still a small leak. 1.0 is good to go. So it’s good enough, I guess. I couldn't locate where the rest of the leak is, as the smoke was coming out as a very, very thinning cloud, whereas with the original smoke test it was more apparent from where it was coming from.

This is the smoke machine i used.
ANCEL S300 Smoke Machine
 
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