mixxy
Member
Can anyone with fairly tech knowledge shead some light here
I still have a rough start on my A2 TDI ( AMF ) its a bit smokey on start up ( White smoke )
I have gone through various test etc and still have soo much to test
Once the car is warmed up it seems to be OK although it feels like its holding back, I replaced all the small vacuum pipes at the rear of the car which made it fly for a while but gradually slowed again
Doing some Diagnostics I appear to have around 7psi of boost at idle , Overboost ?
So would assume this could cause the car to overfuel at startup and thus white unburnt diesel
Even with the n75 unplugged I have 6-7psi of boost, could it be the boost sensor ?
My brothers AMF Polo reads 0.5 - 1.0 vac at idle which I understand is correct
Is there a boost sensor somewhere to clean or replace
If i unplug my MAF sensor I get 21.0 vac at idle !!?
With the logs I have it could diag a bad MAF, I cant attach a XLS on here but one reading exampe on the motorway would be
Engine RPM(rpm) Mass Air Flow Rate(g/s) Turbo Boost & Vacuum Gauge(psi)
2751 67.16000366 17.80368996
2817 88.05999756 27.8257885
2817 82.44000244 24.17903137
2861 82.44000244 24.17903137
2884 83.68000031 24.15689659
2884 83.13999939 23.59826088
2901 83.13999939 23.59826088
2913 84.62000275 24.0515976
2913 84.19999695 23.70041275
2911 84.19999695 23.70041275
Im still unsure except to sort this overboost out
Then check timing ( loging is saying -3.5 ) - this could be cam sensor
I still have a rough start on my A2 TDI ( AMF ) its a bit smokey on start up ( White smoke )
I have gone through various test etc and still have soo much to test
Once the car is warmed up it seems to be OK although it feels like its holding back, I replaced all the small vacuum pipes at the rear of the car which made it fly for a while but gradually slowed again
Doing some Diagnostics I appear to have around 7psi of boost at idle , Overboost ?
So would assume this could cause the car to overfuel at startup and thus white unburnt diesel
Even with the n75 unplugged I have 6-7psi of boost, could it be the boost sensor ?
My brothers AMF Polo reads 0.5 - 1.0 vac at idle which I understand is correct
Is there a boost sensor somewhere to clean or replace
If i unplug my MAF sensor I get 21.0 vac at idle !!?
With the logs I have it could diag a bad MAF, I cant attach a XLS on here but one reading exampe on the motorway would be
Engine RPM(rpm) Mass Air Flow Rate(g/s) Turbo Boost & Vacuum Gauge(psi)
2751 67.16000366 17.80368996
2817 88.05999756 27.8257885
2817 82.44000244 24.17903137
2861 82.44000244 24.17903137
2884 83.68000031 24.15689659
2884 83.13999939 23.59826088
2901 83.13999939 23.59826088
2913 84.62000275 24.0515976
2913 84.19999695 23.70041275
2911 84.19999695 23.70041275
Im still unsure except to sort this overboost out
Then check timing ( loging is saying -3.5 ) - this could be cam sensor