[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

[Kevingro0478]

Originally Posted by 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 [...]

My vehicle, a 2018 F15 N55, is doing the same thing. AND, it seems like it is “self healing”. Or it may be something to do with the air saturation or humidity combined with heat, and then when I put a load on the motor; like you, I drive up a little hill, and boom, it pops a CEL and Drivetrain Malfunction, “power reduced”, and I definitely do have a loss of power/boost. Clearly, it is trying to keep something safe, which it was designed to do. It also tells me that I CAN continue driving. I never lost power though, meaning, my motor has never shut off like yours while I was driving. Unfortunately I don’t have ISTA yet, I’m still working on a laptop that I plan to use. What I really would like to do is all the topside adaptations, including Valvtronic, throttle, Steering, everything I can.

Originally, my issue started after my water pump was replaced because it was staying on and draining the battery. The dealership swapped the water pump and then said they couldn’t start my vehicle once the battery was charged. They had told me that there had fault that told them that the accentric shaft was jammed, (why the car wouldn’t start) and that there is a procedure on ISTA to unjamm it by hand. Which I believe they did. BUT, I think that when the battery dies, or when it’s below a certain voltage and amperage, it que’s the systems to shut down to save energy, INCLUDING Valvtronic, which is why it was jammed and why the car wouldn’t start. But once they unjammed it, I don’t think they did a Valvtronic adaptation to reset or “relearn”. Z All that trying to start the car probably through off the eccentric shaft. And, when I returned the car for this “jerking” issue, they charged the battery sufficiently and although it is only 8 months old, it still drained probably 6 times before I could get it to the dealership to have it repaired. And when i got the car back, having only driven a mile down the road, the motor started to exhibit a jerking effect. Also, the key fob and TPMs were not working at all either when I picked up my car from the dealership.

I read and watched some videos that explained that when the battery is drained éit will shut down these systems. But then they have to be reset, which the stealership didn’t do. So after a bunch of research, I troubleshot it myself, and everything looked fine in the systems, AND THEY WERE ALL WORKING BEFORE THE STEALERSHIP TOUCHED IT. I believe that since they knew the battery was drained, they should have electrically reset everything in the car, including adaptations. So when I got the car back, I went ahead and disconnected BOTH batteries for about 30 minutes, and I discharged the systems by connecting positive with negative for a few minutes, to essentially do a reset. And although the car still does the jerking action, the keyfob and TPMS work again with no issues. I am almost positive that if I can do an adaptation on the rest of the systems that require them as a “reset” or “relearn”, then my issue will be fixed. BUT, that’s if the Valvtronic didn’t cause my plugs to foul from being out of alignment, or however you want to call it when it needs to be “relearned”. I’m seeing a guy this weekend to hopefully do adaptations. I’ll post when I have my results.

[David Kunitz]

Originally Posted by Kevingro0478

My vehicle, a 2018 F15 N55, is doing the same thing. AND, it seems like it is “self healing”. Or it may be something to do with the air saturation or humidity combined with heat, and then when I put a load on the motor; like you, I drive up a little hill, and boom, it pops a CEL and Deivtrain Malfunction, definitely loss of power/boost. Clearly, it is trying to keep something safe, which it was designed to do. It also tells me that I CAN continue driving. I never lost power though. My motor has never shut off like yours while I was driving. Unfortunately I don’t have ISTA yet, I’m still working on a laptop that I plan to use. What I really would like to do is all the topside adaptations, including Valvtronic, throttle, Steering, everything I can.

Originally, my issue started after my water pump was replaced because it was staying on and draining the battery. The dealership swapped the water pump and then said they couldn’t start the vehicle. They said there was a fault that told them that the accentric shaft was jammed, (why the car wouldn’t start) and that there is a procedure on ISTA to unjamm it by hand. Which I believe they did. BUT, I think that when the battery dies, and when it’s not at a certain voltage and amperage, it que’s the systems to shut down to save energy, INCLUDING Valvtronic, which is why it was jammed and why the car wouldn’t start. But once they unjammed it, I don’t think they did a Valvtronic adaptation to reset it. All that trying to start the car probably through off the eccentric shaft. And, when I returned the car for this “jerking” [...]

Very interesting read. I wouldn't be surprised if resetting adaptations would solve the issues you are experiencing.

But isn't your dealership responsible for doing so, as they were the people who caused these issues in the first place?

I too have been trying to get my hands on ISTA+ for a long time now, but no luck yet.
If I do manage to figure it out I'll get in touch with you and try get it right your side as well.

As for my 335i it was a simple issue that I solved by putting fuel in the car

When my car read just above 1/4 tank of fuel it would start to jerk and then stall. (Running out of fuel)

I realised that the fuel in the left tank was not able to be Pumped over to the right tank where the fuel pump is located. Causing the car to run low on fuel so early.

For now I am still trying to figure out how to solve this issue but if I keep the car above 1/4 tank it is safe.

If you manage to reset your car or have the problem solved another way please let me know.
I do hear many people talking about their water pumps draining their battery's in these cars...

[Kevingro0478]

Originally Posted by David Kunitz

Very interesting read. I wouldn't be surprised if resetting adaptations would solve the issues you are experiencing.

But isn't your dealership responsible for doing so, as they were the people who caused these issues in the first place?

I too have been trying to get my hands on ISTA+ for a long time now, but no luck yet.
If I do manage to figure it out I'll get in touch with you and try get it right your side as well.

As for my 335i it was a simple issue that I solved by putting fuel in the car

When my car read just above 1/4 tank of fuel it would start to jerk and then stall. (Running out of fuel)

I realised that the fuel in the left tank was not able to be Pumped over to the right tank where the fuel pump is located. Causing the car to run low on fuel so early.

For now I am still trying to figure out how to solve this issue but if I keep the car above 1/4 tank it is safe.

If you manage to reset your car or have the problem solved another way please let me know.
I do hear many people talking about their water pumps draining their battery's in these cars...

Thank you for your reply. So, you’d think that the dealership woukd fix something that they clearly had caused, but no. Instead, they did a tiny bit of diagnosing, and since the tech had to allegedly “unjamm” the eccentric shaft by hand the first time around, he then proceeded to wrote a $9500 estimate for the replacement of the shaft when I retuned to the dealership the next day for all the new issues. Just the key fob/Tpms repair estimate was over $700. So, again, thank you for your reply. And if you do happen to get ISTA loaded on a device, then I am all ears! Take care

[F30 Mike]

I have the same issue with my 2013 335xi Sep 2012 build. I was able to make it home with no issues in ECO Pro mode haven’t tried that since.
Originally I had a valvetronics code with it, so I changed the essentric shaft and valvetronic actuator, which was only 2 years old, and the valvetronics code went away but the startup valvetronic relearn process kills the engine every time the actuator starts moving.
Next I ran the valvetronic stop limit relearn and the engine still shuts off but the relearn process continues on and passes every timeline nothing happened.
Sometimes I can drive the car for an hour and not have any issues, other times I get the drivetrain malfunction within 30 minutes. Today I started it and I got the drive train malfunction at idle within a few seconds and the engine shut off twice.
Chat GPT thinks it’s the DME miss interpretation of wheel speed data coming from the ICM due to a bad driver in the DME. I didn’t want to hear that so I pulled every fuse in every fuse box one at a time, removed mild corrosion and tested them with no issues.
I checked the power supply under the hood on the drivers side, ICM, IBS, terminals 20 & 30, battery, & alternator health with a multi meter and ISTA+ test modules. Also checked the DME wire harnesses and pins on the harnesses and DME, VANOS cam adjustment gears and VVT system using ISTA+ test modules with no issues.
I changed the VANOS solenoids even though they were clean just because they were never changed, replaced the wire harness for the essentric shaft shaft actuator and the chassis ground strap near the catalytic converter just to eliminate any other potential electrical system variables with no improvement.
“I tried to data log it with Bootmod3 but connectivity is lost at the OBDII port once the speedometer and tach needles start to sweep and engine power cuts.”
There are no permanent codes that point to a specific component and all systems check good including the DME test module in ISTA+.
At this point I think I’ve checked all that I can check without an oscilloscope so Chat GPT has my attention.
I decided to plug in a scan tool to record wave function data for wheel speed just to see if I saw anything odd since ChatGPT highlighted the possibility of that data being misinterpreted and the OBDII port reads that data from the DME, which receives it’s data from the ICM, after the wheel speed data has already been processed by the ICM and I saw readings that suggested 1 wheel wheel was moving 30 MPH faster than the others. I saw this with multiple wheels at different points in the recording. I did not see that when I was looking at it, but it showed in the recording, I was driving so I didn’t want to stare at it. I don’t think the wheel speed sensors are the problem since I have codes for all of them so GPT might be right and I can’t get my ISTA+ “full PSdZData” to load properly so I can program a refurbished DME.
See the image below for the codes I get, in ISTA+ only, after the drive terrain malfunction asserts, they are the same codes I get when the startup valvetronics run in module in ISTA+ kills the motor. Ignore the first 3, oil pressure only hit that one time, SINE is the internal siren battery which I’ve had no issues with and it passed its test module, the connection issue is due to an aftermarket head unit.
I’ll post in here when I change the DME for an update good or bad.

Mods:

1. Precision Raceworks
2. F-Series High Performance low pressure Fuel Pump - Stage 3.
3. High Performance Ignition Kit
4. Turner
5. Performance Open Intake
6. High Flow Catalytic Converter
7. Pure Turbos PURE750 Turbocharger Upgrade - N55 PWG
8. Dorch stage 2 HPFP
9. Upgraded metal charge pipe, turbo inlet and outlet pipe.
10. Dinan axel back exhaust.
11. Bootmod3 custom tune with transmission flash, 93 octane.