Mk1_Oz
26th June 2019, 09:29 AM
I have done a fair amount of Dr Google research on this topic which indicates that my HPFP might be failing in some way. At a quoted replacement price of $5,500 I want to do some research and make the correct decision!! What do you think from the below?
Symptoms:
When driving under light load and usually around 60kph type speeds the dash lights up with several yellow icons, I get an F where the gear indicator is and it bing bongs. The car loses power. About 6 seconds later there is another bing bong and more error messages get displayed and all power is lost (suspension lowers, stability and roll control faults). I have to pull over (somehow!), turn the car off, restart and all is good. I get the same 8 faults every time. The main one is low fuel pressure and the others are all about data errors and communications faults. This never happens when the car is cold and seems to happen more when things are hot (say after going up hill) and also doesn't happen under higher loads. Pretty much seems to be when a tiny throttle increase is made at around 60kph. It seems that once the fault starts I will get many faults in a row, sometimes only going 1/2km before the next bing bong but other times it does not happen at all.
What Have I Tried:
Putting the trans into sport mode and therefore using a lower gear helps. Trying not to make small throttle increases helps but makes the car horrible to drive (very stop go). I did have some success with having a full tank of fuel but even then it happened a couple of times. My indy dealer took a look and as expected said the HPFP needed replacing. They did not provide me with any data to back that up though. They did say that it is likely one of the pump solenoids sticking and that a HPFP test showed great pressures. My Nanocom seems pretty much useless in this instance as it only has a live data PID for the fuel pressure but nothing about the Volume Control Valve (VCV) or thge Pressure Control Valve (PCV). I have a cheap Foxwell NT624 unit that logs data but again does not have the required PIDs. The battery has been checked.
My Thoughts:
Given that the issue seems to only be when commanding a slight increase in fuel to the engine my thoughts are that the PCV is sticking. When commanding a big fuel increase (big throttle move) the PCV solenoid is commanded to open alot to keep the fuel pressure up. When commanding a small fuel increase it only needs to move a small amount and seems to stick. Not sure if the solenoids are current controlled or pulse width modulation controlled but it might seem that it handles a bigger change better. It could be the fuel rail pressure sensor failing but I feel this is unlikely as the isue is only when a small fuel increase is required whereas with a failing pressure sensor it would happen all the time.
Questions:
Is there a way of better logging what the fuel pump is doing so that the problem can be isolated?
Has anybody found a way of getting these fuel pumps overhauled with new solenoids (diesel specialist)?
Anybody had anything similar?
I rang the Adelaide stealer parts centre to check the price that the indy had given me and although the price was the same ($4500 for the pump) the stealer said they have not sold any. Makes me wonder if these can be overhauled or if the issue is actually elsewhere otherwise they surely would have sold a heap........
Symptoms:
When driving under light load and usually around 60kph type speeds the dash lights up with several yellow icons, I get an F where the gear indicator is and it bing bongs. The car loses power. About 6 seconds later there is another bing bong and more error messages get displayed and all power is lost (suspension lowers, stability and roll control faults). I have to pull over (somehow!), turn the car off, restart and all is good. I get the same 8 faults every time. The main one is low fuel pressure and the others are all about data errors and communications faults. This never happens when the car is cold and seems to happen more when things are hot (say after going up hill) and also doesn't happen under higher loads. Pretty much seems to be when a tiny throttle increase is made at around 60kph. It seems that once the fault starts I will get many faults in a row, sometimes only going 1/2km before the next bing bong but other times it does not happen at all.
What Have I Tried:
Putting the trans into sport mode and therefore using a lower gear helps. Trying not to make small throttle increases helps but makes the car horrible to drive (very stop go). I did have some success with having a full tank of fuel but even then it happened a couple of times. My indy dealer took a look and as expected said the HPFP needed replacing. They did not provide me with any data to back that up though. They did say that it is likely one of the pump solenoids sticking and that a HPFP test showed great pressures. My Nanocom seems pretty much useless in this instance as it only has a live data PID for the fuel pressure but nothing about the Volume Control Valve (VCV) or thge Pressure Control Valve (PCV). I have a cheap Foxwell NT624 unit that logs data but again does not have the required PIDs. The battery has been checked.
My Thoughts:
Given that the issue seems to only be when commanding a slight increase in fuel to the engine my thoughts are that the PCV is sticking. When commanding a big fuel increase (big throttle move) the PCV solenoid is commanded to open alot to keep the fuel pressure up. When commanding a small fuel increase it only needs to move a small amount and seems to stick. Not sure if the solenoids are current controlled or pulse width modulation controlled but it might seem that it handles a bigger change better. It could be the fuel rail pressure sensor failing but I feel this is unlikely as the isue is only when a small fuel increase is required whereas with a failing pressure sensor it would happen all the time.
Questions:
Is there a way of better logging what the fuel pump is doing so that the problem can be isolated?
Has anybody found a way of getting these fuel pumps overhauled with new solenoids (diesel specialist)?
Anybody had anything similar?
I rang the Adelaide stealer parts centre to check the price that the indy had given me and although the price was the same ($4500 for the pump) the stealer said they have not sold any. Makes me wonder if these can be overhauled or if the issue is actually elsewhere otherwise they surely would have sold a heap........