Mk5 GTi stage 1 fuel pressure problems

[Lassebongo]

Alright im back with the logs including the lambda. I swapped back to the newer pump again and it seems to fit just fine now, dont know what i did wrong before..

https://log.tunezilla.com/s/0um1L1Wt

Now with all the swapped parts and the pump is fitted nicely in the tank hole the car threw some fault codes aswell. Makes sense but i think all the swapped parts were culprits aswell. The mesh filter in the old pump was completely clogged, tried soaking it in breakcleaner etc but made no difference. The car is drivable now but just a tad bit to much on the pedal it starts jerking.  Im assuming the pump is pushed to 91% because of the nonsense values the g410 is giving the ECU.

4 Faults Found:
 000307 - Oxygen (Lambda) Sensor B1 S1
               P0133 - 002 - Response too Slow - Intermittent
             Freeze Frame:
                    Fault Status: 00100010
                    Fault Priority: 2
                    Fault Frequency: 1
                    Reset counter: 255
                    Mileage: 133420 km
                    Time Indication: 0
                    Date: 2000.00.00
                    Time: 05:02:06
             Freeze Frame:
                    RPM: 1417 /min
                    Load: 33.7 %
                    Speed: 57.0 km/h
                    Temperature: 73.0°C
                    Temperature: 41.0°C
                    Absolute Pres.: 980.0 mbar
                    Voltage: 13.716 V
 012555 - Low Pressure Fuel regulation
               P310B - 002 - Fuel Pressure Outside Specification - Intermittent
             Freeze Frame:
                    Fault Status: 00100010
                    Fault Priority: 2
                    Fault Frequency: 49
                    Reset counter: 255
                    Mileage: 133441 km
                    Time Indication: 0
                    Date: 2000.00.00
                    Time: 08:08:45
VCDS
 Diagnostic Trouble Code Report
 Control Module Part Number: 1K0 907 115 Q
 Page 2
             Freeze Frame:
                    RPM: 2116 /min
                    Load: 9.4 %
                    Speed: 0.0 km/h
                    Temperature: 46.0°C
                    Temperature: 27.0°C
                    Absolute Pres.: 1010.0 mbar
                    Voltage: 14.097 V
 000135 - Fuel Rail/System Pressure
               P0087 - 002 - Too Low - Intermittent - MIL ON
             Freeze Frame:
                    Fault Status: 10100010
                    Fault Priority: 2
                    Fault Frequency: 32
                    Reset counter: 255
                    Mileage: 133454 km
                    Time Indication: 0
                    Date: 2000.00.00
                    Time: 06:54:39
             Freeze Frame:
                    RPM: 917 /min
                    Load: 29.0 %
                    Speed: 0.0 km/h
                    Temperature: 29.0°C
                    Temperature: 20.0°C
                    Absolute Pres.: 1000.0 mbar
                    Voltage: 13.843 V
 009529 - Low Pressure Fuel Sensor (G410)
               P2539 - 001 - Open Circuit - Intermittent
             Freeze Frame:
                    Fault Status: 00100001
                    Fault Priority: 2
                    Fault Frequency: 1
                    Reset counter: 255
                    Mileage: 133749 km
                    Time Indication: 0
                    Date: 2000.00.00
                    Time: 02:58:22
             Freeze Frame:
                    RPM: 0 /min
                    Load: 0.0 %
                    Speed: 0.0 km/h
                    Temperature: 31.0°C
                    Temperature: 38.0°C
                    Absolute Pres.: 990.0 mbar
                    Voltage: 11.938 V

[ZoliWorks]

Did you clear the codes after fitting everything back and then go for a test drive?

[Lassebongo]

Sure did. They came back. The check engine light seems sporadic though, does not come back right away.
I'm doing a live log tomorrow while jiggling the connector. Also cleaning the pins inside the connector plus the counterpart on the sensor

[Lassebongo]

ok so problem persists... ive swapped the seal to the pump and the g410 sensor because of the fault code which is now gone.
Car runs but at first cold start the car stalls after a few seconds, keeping at it until the engine is warmer(choke goes away) it stays on during idle. Barely drivable, just a tad to much on throttle it starts to stall, if i let go of the throttle it stays on but if i keep the throttle on it shuts off. Logs say stable pressure on idle but pressure drops to under 2 bar with a bit of throttle. Is the pump the wrong one ?
This one has a closed top with the filter covering the whole bottom, old one was an open top bucket.


It was marked with the part number 1K0919051DB when i bought it.

I also tested with my old pump relay module which showed very erratic swings on the low side pressure. The log posted is with the new relay.
https://log.tunezilla.com/s/s4O0EhMs