Hello,
long time reader of this website along others dedicated to Audi, I’ve decided to create an account and ask for a bit of help as it seems the community here is pretty knowledgeable and helpful ! Not sure if there’s a presentation thread but here I am. Beware, long post incoming :
So, I currently own a 2010 Audi A5 Coupe (B8, pre-facelift, 2.0 TDI 163 Hp - CAHB engine) for over a year, got the car at 153.000 km, currently sits at 182.000ish km.
I’ve been dealing with lots of minor problems on the car but thankfully nothing mechanical or serious yet, tho I’m afraid that might come into play sooner than later due to age/km count and some warnings signs IMO. One of them is the high pressure fuel pump.
For the whole ownership of the car I have always noticed a rattle coming from the engine bay, without being sure of its origin, noise is the same as on this video :
It can be heard while stationary and reving, or while driving at low speed with windows opened. At higher speeds the engine noise drowns it out. Doesn’t seem to be audible at idle
I firstly suspected some valve at the back of the engine (Siemens VDO - butterfly valve, throttle body I think ?) which if I’m not mistaken has a module with plastic gears that can get noisy, but after further searching I’m 99% sure the noise comes front the front, exactly where the HPFP is. (It’s possible the mentioned other valve makes a bit of noise but that’s for later).
The car doesn’t seem to behave strangely, drives normally, no error codes (I have a OBD Eleven scanner and check regularly), no dash light.
Oil is changed every 15.000km, along with fuel filter, oil filter, cabin filter, etc.
Important info : The timing belt kit has been changed (belt, tensioners, water pump) immediately after getting the car, and according to the documents this car has been subjected to the VW recall and remap due to the dieselgate. I mention this because I’ve read some people reporting this noise right after one of these operations.
Now I have been racking my head around this for the past days as you can read anything and everything about this : “it’s normal all TDI engines from VAG group do the same”, “it’s not normal HPFP has to be replaced”, “I’m not sure but car is fine so I leave it”, ….
In my opinion i believe that part of it is normal operating noise especially considering the age but I also believe such moving components wear down, and with this comes a big concern : METAL SHAVINGS. I have been reading lots of horror stories and I would like to avoid this at all cost !
I have read my car is fitted with a Bosch “CP4” pump and these are known to fail that way. Unfortunately I’m currently in no financial position to replace it, so in the meantime I would like to at least keep an eye on it and check for metal shavings in the fuel system. The problem is, how ?
I thought about removing the fuel pressure regulator that sits on top of the pump and check the tiny fuel well for metal shavings since there’s just two screws and it seems like the easiest but I stopped immediately after reading again many horror stories about people that didn’t bleed the system/relieve the pressure, or introduced air in the system by doing so, resulting in a car that wouldn’t crank anymore and in some cases, killing the whole HPFP.
So, is there a proper procedure to do this without any risk of damage ? Am I better off just leaving it like that until I get symptoms of HPFP failure ? The problem is that I guess if I wait and encounter symptoms, it will be too late and I’m not sure how I would deal with having to replace the whole fuel circuit considering the steep cost.
If the noise is truly nothing to be worried about, it’s even more complicated because there is basically no way to tell if something is (starting to be) wrong or not…
thanks for anyone that read this !
long time reader of this website along others dedicated to Audi, I’ve decided to create an account and ask for a bit of help as it seems the community here is pretty knowledgeable and helpful ! Not sure if there’s a presentation thread but here I am. Beware, long post incoming :
So, I currently own a 2010 Audi A5 Coupe (B8, pre-facelift, 2.0 TDI 163 Hp - CAHB engine) for over a year, got the car at 153.000 km, currently sits at 182.000ish km.
I’ve been dealing with lots of minor problems on the car but thankfully nothing mechanical or serious yet, tho I’m afraid that might come into play sooner than later due to age/km count and some warnings signs IMO. One of them is the high pressure fuel pump.
For the whole ownership of the car I have always noticed a rattle coming from the engine bay, without being sure of its origin, noise is the same as on this video :
It can be heard while stationary and reving, or while driving at low speed with windows opened. At higher speeds the engine noise drowns it out. Doesn’t seem to be audible at idle
I firstly suspected some valve at the back of the engine (Siemens VDO - butterfly valve, throttle body I think ?) which if I’m not mistaken has a module with plastic gears that can get noisy, but after further searching I’m 99% sure the noise comes front the front, exactly where the HPFP is. (It’s possible the mentioned other valve makes a bit of noise but that’s for later).
The car doesn’t seem to behave strangely, drives normally, no error codes (I have a OBD Eleven scanner and check regularly), no dash light.
Oil is changed every 15.000km, along with fuel filter, oil filter, cabin filter, etc.
Important info : The timing belt kit has been changed (belt, tensioners, water pump) immediately after getting the car, and according to the documents this car has been subjected to the VW recall and remap due to the dieselgate. I mention this because I’ve read some people reporting this noise right after one of these operations.
Now I have been racking my head around this for the past days as you can read anything and everything about this : “it’s normal all TDI engines from VAG group do the same”, “it’s not normal HPFP has to be replaced”, “I’m not sure but car is fine so I leave it”, ….
In my opinion i believe that part of it is normal operating noise especially considering the age but I also believe such moving components wear down, and with this comes a big concern : METAL SHAVINGS. I have been reading lots of horror stories and I would like to avoid this at all cost !
I have read my car is fitted with a Bosch “CP4” pump and these are known to fail that way. Unfortunately I’m currently in no financial position to replace it, so in the meantime I would like to at least keep an eye on it and check for metal shavings in the fuel system. The problem is, how ?
I thought about removing the fuel pressure regulator that sits on top of the pump and check the tiny fuel well for metal shavings since there’s just two screws and it seems like the easiest but I stopped immediately after reading again many horror stories about people that didn’t bleed the system/relieve the pressure, or introduced air in the system by doing so, resulting in a car that wouldn’t crank anymore and in some cases, killing the whole HPFP.
So, is there a proper procedure to do this without any risk of damage ? Am I better off just leaving it like that until I get symptoms of HPFP failure ? The problem is that I guess if I wait and encounter symptoms, it will be too late and I’m not sure how I would deal with having to replace the whole fuel circuit considering the steep cost.
If the noise is truly nothing to be worried about, it’s even more complicated because there is basically no way to tell if something is (starting to be) wrong or not…
thanks for anyone that read this !
