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mihaiti
6th September, 2023, 02:31 PM
Hello, i have this Sprinter from 2016 with FSCU when the low pressure is disconnected, the cars starts and revs up to 3000 rpm!
With this sensor connected the cars does not start at all!
With the sensor disconnected i have error on fscu 254100 (the pressure sensor is disconnected)!
Low fuel pressure shows between 0-4bars,when pump is on, data is shown in fscu and ecu. When crancking pressure shows 4bar but rail pressure shows 0-1 bars and car does not start. If i remove the connector from low pressure sensor car starts instantly!
REAL pressure measured here with manometer is 5,1 bars so the lower fuel pump is working fine,

When i plug the fuel pressure sensor witch goes to fscu2 , near fuel filter the car does not start anymore, the car cranck but no start with no errors in engine ecu!!!Communication works between these 2 because i can see the low fuel pressure in the ecu and fscu2!