[David Kunitz]

Hello everyone!

I will apologise for the long story in advance

I recently purchased a very high milage 335i F30.
*Build date April 2012*

I pushed the car like crazy on the test drive and it felt great other than the suspension which is not an issue for me right now.

When driving it home, I continued to floor it and it felt really good however I ended up going up an uphill and while pushing the accelerator about 20% or less I had a full power cut for about 1 to 2 seconds and the car came back, no engine lights or anything just a sudden loos of power.
Luckily I made it home with no other issues!

The next day I did an oil change and cleaned the vehicle inside and out, I didn't mess with anything else on the car.

Now today I drove it for just 5km to the shops and back, I have a few decent hills just outside my gate and it went up gently and made it to the shops without an issue.

I then was on my way home, everything seemed fine until I came across another steep hill, I was once again only 15% to 20% throttle and it did the same thing as it did 2 days before *a power cut and then it came back*

I then was on a slight incline with very minimal throttle 5% and it did the same thing yet again (DSC OFF THAT TIME)

After that I had a stop street on a steep incline and as I was driving up very gently 20% throttle the car lost it's power yet again and this time it completely stalled and put me in neutral as I came to a stop.
It started back up without an issue and I drove up the rest of the hill and on a small flat surface then rolled downholl without any issues.

On the last incline before my steep driveway I had some speed to start with and was using more throttle than before and nothing went wrong.

Then the last part was my very steep driveway which is also narrow, so as I was slowly crawling up the car stalled again, I restarted it again and only 5 meters later it stalled again.
I restarted it yet again and made it to a level surface outside my house.

*When I test drove the car I was driving up steep hills the whole time but I was pushing the car hard and nothing went wrong.

As I am editing this message the car has been idling, it shuddered a little and then stalled again, so I guess it does it on idel as well

I have been thinking that perhaps the HPFP is the issue but I would thoroughly appreciate anyone's advice on what this issue could be.

If you need more information about the vehicle or the driving situation please let me know!

[fijigabe0]

When you test drove the car, what was the level of the fuel tank? I'm assuming it was full, correct? I think there's an issue with the in-tank fuel pump, pickup or sending unit. Something there is starving for fuel when at an incline. Try filling up the tank and testing it again and see if the problem goes away. If it does, then the problem is in the tank.

[David Kunitz]

Originally Posted by fijigabe0

When you test drove the car, what was the level of the fuel tank? I'm assuming it was full, correct? I think there's an issue with the in-tank fuel pump, pickup or sending unit. Something there is starving for fuel when at an incline. Try filling up the tank and testing it again and see if the problem goes away. If it does, then the problem is in the tank.

It had a half tank when I test drove the car, and today I actually bought 5 liters and put it in the car as it didn't start anymore.

After some fuel it ran beautifully, I guess there is an issue with the feul gauge.

I can not be sure yet as after the 3rd start since the fuel it didn't want to start, however I had the ignition on for a while when I reset the break service light, perhaps that could have affected the fuel pressure?

Many thanks for your advice, I truly appreciate it