Big problem. Looks like misfire

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piterus87

Greenie N00B Member
Hello everyone.
My English is not perfect so I have to help myself with a translator.
I have a big problem with my mazdaspeed3 / MPS. maybe someone will think of something or have had a similar action with his car.
Patient: 3 MPS BK / Mazdaspeed3
Symptoms: After starting the car, it shakes a lot when it is cold, it is like 3.5 cylinders, it farts and farts from the exhaust. Symptom similar to a misfire or mega leak in the intake. Zero errors.
What I have already checked / replaced:
- MAF x3,
- regeneration of 3 injections + one new one + new washers
- crank sensor and shaft sensor - replacement for another
- MAP sensor - new from Bosch
- a set of coils - 2 sets of new spark plugs
- second harness for coils
- cleaned EGR
- inlet valves cleaned
- new original lambda sensor (the one in front of the catalyst)
- proven compression probably 6 times - anywhere between 12 and 12.5 bar
- Solenoid from the vacuum in the inlet - replacement for another used one.
- pressure test of the entire inlet - small leakage at the PVC valve - eliminated
I probably forgot to mention something above because that was it, but I replaced most of it.
After regeneration of the injectors for about a week, the car drove almost normally (it felt very gently, as if it was cutting its power slightly, but it was possible to drive). After this time, I replaced the spark plugs with new ones and the problem came back again (I think it's just a coincidence). The return to the old candles did not help, the exchange for another new set - also no effects. I'm starting to spread my hands because all the potential causes have theoretically been eliminated and the car is still working like shit and I can't drive it.
STFT normal, fuel pressure normal, pump pressure in the tank is approx. 4 bar on the rail
I do not know if it is possible that any injection after regeneration died so quickly? Injections regenerated about a month ago.
Below is a video of how he works after a cold start.
I will be grateful for all suggestions on what could be the cause or what I should check

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do you have a way of monitoring fuel pressure and have you done any maintenance to the high pressure fuel pump?
 
yes, I have Autotech internals installed.
I have a preview of all parameters. The fuel rail pressure on the KOEO is approximately 55-58 PSI. After starting the engine, the pressure increases immediately to about 1660 PSI (cold start) and drops to about 430 - 435 PSI at idle, when the engine is warmed up

I will add that when I disconnect the MAF, the engine works better, but then the engine adds fuel because the AFR holds about 13 - 13.2. It looks as if the engine is not getting enough fuel. After connecting the MAF, the engine starts to run badly but the AFR is perfect 14.7
 
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Are you using oem mafs? Other brands are know to just not work correctly

If unplugging the mad makes it run fine it is probably the MAF. Do you know someone local so you could swap with a known good one
 
I have 3 MAFs all original, used. unfortunately, replacing them has no effect. disconnecting the Maf only improves idling, after increasing the revs the car starts to choke and snort. maybe it's a normal symptom, I don't know..
 
I am posting logs from a cold start and the operation of a warm engine. Maybe someone will notice something abnormal. I have no idea what could be wrong ... I am only wondering about very large fluctuations in the ignition timing
 

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