Mps sputtering

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MPS

MPS

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Hello everyone, i have some problems with my Mazdaspeed 3 bk, maybe you can help me.. i replace the turbo, everything was fine, couple of months after replacing i notice that car one day going very well, (slightly over boosting, faults in picture below ), i found that one hose for wastegate solenoid valve isn't attached to intake hose, i connected that hose, car was smooth again but not for long and it started twitching and jerking at aprox 2500-3000 rpms at steady throttle position, it have hesitation when accelerating, and i think no boost or very small boost, no fault codes now..any ideas what to check for? Car is bone stock
 

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I would check the vacuum lines,boost controller too. Post logs if possible.
 
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Raider said:
I would check the vacuum lines,boost controller too. Post logs if possible.
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Thanks for responding, i found the problem, both hoses for intake flaps solenoid are cracked, i replace them, car goes like fury now
 

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Update, intake flaps working, problem is fault p2178, like there's to much fuel, maf sensor reacts, at idle is 3g/s, on 3000 rpms is 12g/s, how much lambda must be? What else to check, don't have tools to do log?
Today i removed battery to get access for egr valve, when i returned it, i do throttle relearning procedure, car after that was smooth in driving, no jerking no sputtering, after turning off engine for 5 minutes and when i turn on again to go home, car again started to behave same, jerking and limiting boost...don't know what to do anymore
 

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Hard to tell with the apparent super low resolution on these logs and no timestamps to get a good idea of how quickly (or not quickly) things are changing.

Idle log:
The LTFTs a little on the high side, just out of spec (which is +- 8%; you have 14) but the STFTs are fine.
Rest of the log looks fine.

WOT log:
The length of this log appears to be 6 rows. That's not gonna cut it for resolution, bud.
It's going rich as hell, but there's no knock sensor column to indicate if that might be the issue or not. Missing a lot of stuff I'm used to seeing in a Versatune or Accessport log file.
Also a lot of stuff in here that doesn't need to be, like the G force meter, O2 sensor voltages, commanded AFRs (why are there two columns for each?)

Ultimately, you're going to need to get some kind of proper logging device with a fast response rate...I remember torque being much faster than this.
 
Enki said:
Hard to tell with the apparent super low resolution on these logs and no timestamps to get a good idea of how quickly (or not quickly) things are changing.

Idle log:
The LTFTs a little on the high side, just out of spec (which is +- 8%; you have 14) but the STFTs are fine.
Rest of the log looks fine.

WOT log:
The length of this log appears to be 6 rows. That's not gonna cut it for resolution, bud.
It's going rich as hell, but there's no knock sensor column to indicate if that might be the issue or not. Missing a lot of stuff I'm used to seeing in a Versatune or Accessport log file.
Also a lot of stuff in here that doesn't need to be, like the G force meter, O2 sensor voltages, commanded AFRs (why are there two columns for each?)

Ultimately, you're going to need to get some kind of proper logging device with a fast response rate...I remember torque being much faster than this.
Click to expand...
Thanks for your time to see it, i don't have versatuner or accessport unfortunately but i will find better tool to do logs, what you need specifically?
After a short drive my LFTT jumped to - 17, i tried to touch maf wires on connector, and LTFT immediately dropped to - 8, maybe maf is problem.. Any ideas how to test my injectors for leaking?
 
Leaky injectors would be a much bigger issue than 17%, but I have had the MAF issue before. Gotta cut and swap the connector, or repin it or something probably.
 
Enki said:
Leaky injectors would be a much bigger issue than 17%, but I have had the MAF issue before. Gotta cut and swap the connector, or repin it or something probably.
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Injectors will be pain in the.. to find replacement, i will order new maf, only denso is available but i hope it will be okay, o2 sensor seems to be respond well, only strange thing that i notice is after turbo rebuild, turbo is very noisy on boost, like unbalanced, and next day when cars running fine, can't hear turbo on acceleration, and I have stronger acceleration
 
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