[SC435i]

Today I got a "Fuel Supply" warning on my dash. At first, the car started and idled for a second before displaying the error, but when I attempted to turn on the car again the engine wouldn't turn over. I tried searching the forum for an answer but it seems this isn't a common issue. I grabbed a datalog and noticed the HPFP target was over 1000 while HPFP actual was closer to 120. Would this indicate a HPFP issue or is this normal?

The car is FBO with meth and Dinan turbo at ~56k miles.


https://www.bootmod3.net/log?id=5f44...90c6667a2d6679

[thejeremyman9]

It looks like the log is just you cranking the car trying to start it?

What codes do you get from BM3?

It's not clear if HPFP being below target is because you have a actual fuel supply issue or if you just didnt get enough RPM yet to build pressure to target... one would think cranking it over it would reach target but i can't say with certainty since ive never seen a log of cranking before.

Having said that the easiest thing to check first is probably LPFP to make sure that is turning on and flowing as it should. If it is, then move on to HPFP.

You also didnt give any context... miles on car? Full mod list? etc

[SC435i]

BM3 didn't give me any codes, the error message was displayed on the Idrive screen but the scan returned nothing. How would you recommend checking the LPFP and the HPFP? As for context, it’s right there at the bottom of my post, but if you didn’t see it I have ~56k miles, fbo, meth, and dinan turbo.

[thejeremyman9]

Originally Posted by SC435i

BM3 didn't give me any codes, the error message was displayed on the Idrive screen but the scan returned nothing. How would you recommend checking the LPFP and the HPFP? As for context, it’s right there at the bottom of my post, but if you didn’t see it I have ~56k miles, fbo, meth, and dinan turbo.

I am not sure the 'official' diagnostic procedure for checking LPFP but you might be able to find it on a google search. The basic way is to check or have someone check to see if they can hear the LPFP when you try to prime or start the car.

Checking the HPFP might be more difficult and dangerous considering the potential pressures involved. I would check for an official procedure.

Sorry not sure how i missed that.

[D1rty_b1rd]

Ran into this issue a few months back. Very similar set up before i switched to speedtech. I had a stage 2 LPFP from fuel-it with a walbro 525. It burned the fuel pump fuse in the trunk. Replaced it. Then it burned out my EKP (wires closest the EKP were a slightly different color). I ended up buying the EoS BPM4 fuel controller.

Turns out that the walbro 525 draws a lot more power and burned out the EKP.

[thejeremyman9]

Originally Posted by D1rty_b1rd

Ran into this issue a few months back. Very similar set up before i switched to speedtech. I had a stage 2 LPFP from fuel-it with a walbro 525. It burned the fuel pump fuse in the trunk. Replaced it. Then it burned out my EKP (wires closest the EKP were a slightly different color). I ended up buying the EoS BPM4 fuel controller.

Turns out that the walbro 525 draws a lot more power and burned out the EKP.

Frying EKP is common with LPFP upgrade but OP doesn't have one?

[SC435i]

I just heard from my mechanic and apperently it was a fried EKP. I thought EKP failure only happened with upgraded pumps too, but apperently it can burn out over time if youre tunned.

[harkes]

Originally Posted by SC435i

I just heard from my mechanic and apperently it was a fried EKP. I thought EKP failure only happened with upgraded pumps too, but apperently it can burn out over time if youre tunned.

Thanks for sharing. Funny how 3 years ago everyone would upgrade their LPFP before anything else and now we know that the stock can support plenty of power. I also have a Walbro 450 LPH in stock.....will not be needing that anymore

[SC435i]

Ok an update: The EKP was replaced successfully, but the car still stalls. Now its able to start for a second before stalling and dying. Since it starts I believe the LPFP is working, but based on the situation would this mean the HPFP failed as well?

[thejeremyman9]

Originally Posted by SC435i

Ok an update: The EKP was replaced successfully, but the car still stalls. Now its able to start for a second before stalling and dying. Since it starts I believe the LPFP is working, but based on the situation would this mean the HPFP failed as well?

Do you have datalogging to check rail pressure? What code(s) are you getting?

[zole2112]

Originally Posted by SC435i

Ok an update: The EKP was replaced successfully, but the car still stalls. Now its able to start for a second before stalling and dying. Since it starts I believe the LPFP is working, but based on the situation would this mean the HPFP failed as well?

Mine would do exactly that when my HPFP was going out. I had narrowed it to the HPFP or EKP but I felt the way it was failing pointed to the HPFP which was the issue. Replaced it last fall and no issues since. I did have fuel pressure codes though.