Hello all,
This car had a failed engine previously (first a failed injector nr4 and after replacement a spun rod bearing on cylinder 4). A new block + head was installed, the rest was taken from the failed engine (injectors, hpfp and everything else). After everything was replaced and put together engine turned on and ran but with heavy misfire on cold. I didnt get to record it but engine would shake occasionally like it missed a beat. I have a video here of how it behaves on warm (much better but there is still some misfire):
Notice also there is audible rattle from the DMF (doubt it could affect the misfire like this).
Now, this problem persisted from the old engine. It was exactly the same in this manner, only it had added some knocking to this.
No fault codes, checking the injectors in vcds showed about these values:
-0.1 0.4 -1.05 0.8
After it ran idle for nearly 1 hour, i wanted to do a small test drive. I was driving along all fine until i stepped on the pedal. Car accelerated OK and then suddenly it cut out completely with coil light flashing. Couldnt start after, clean cranking but no start.
Got back to mechanic and he read a low rail fuel pressure p0087 code.
Then we went ahead and did some diagnostic, first I checked the fuel regulator solenoid valve on top of the HPFP for metal and it was all clear.
On cranking VCDS shows 0 bar actual pressure of the rail - strange.
Checking the lift pump and aux electric pump - they work fine, loads of fuel goes through.
We did the injector overflow test - no fuel at all goes into syringes, i guess it supports the 0 bar reading of the rail.
Also we have tried to disconnect the hard line going from HPFP into the rail - there is some fuel going there, but I believe the pressure should be 100s of bars and it's definitely not close to that.
To me it seems like a failed HPFP, but without any metal in the filters, i always heard about metal in the filters when it fails.
Also, might the HPFP already have been bad before engine replacement, causing the misfire like on video?
Thanks for the reading and potential input!
This car had a failed engine previously (first a failed injector nr4 and after replacement a spun rod bearing on cylinder 4). A new block + head was installed, the rest was taken from the failed engine (injectors, hpfp and everything else). After everything was replaced and put together engine turned on and ran but with heavy misfire on cold. I didnt get to record it but engine would shake occasionally like it missed a beat. I have a video here of how it behaves on warm (much better but there is still some misfire):
Notice also there is audible rattle from the DMF (doubt it could affect the misfire like this).
Now, this problem persisted from the old engine. It was exactly the same in this manner, only it had added some knocking to this.
No fault codes, checking the injectors in vcds showed about these values:
-0.1 0.4 -1.05 0.8
After it ran idle for nearly 1 hour, i wanted to do a small test drive. I was driving along all fine until i stepped on the pedal. Car accelerated OK and then suddenly it cut out completely with coil light flashing. Couldnt start after, clean cranking but no start.
Got back to mechanic and he read a low rail fuel pressure p0087 code.
Then we went ahead and did some diagnostic, first I checked the fuel regulator solenoid valve on top of the HPFP for metal and it was all clear.
On cranking VCDS shows 0 bar actual pressure of the rail - strange.
Checking the lift pump and aux electric pump - they work fine, loads of fuel goes through.
We did the injector overflow test - no fuel at all goes into syringes, i guess it supports the 0 bar reading of the rail.
Also we have tried to disconnect the hard line going from HPFP into the rail - there is some fuel going there, but I believe the pressure should be 100s of bars and it's definitely not close to that.
To me it seems like a failed HPFP, but without any metal in the filters, i always heard about metal in the filters when it fails.
Also, might the HPFP already have been bad before engine replacement, causing the misfire like on video?
Thanks for the reading and potential input!
