Hi everyone!

I have been lurking on this forum for almost a month now, trying to ascertain some issues with a new to us 2012 R56 with the N18 engine (turbo). I bought it 7/3/2023 and drove it for two weeks. Put gas in it at Chevron, and ever since then, it has been in our garage more than it has been on the road. I bought a new code reader specifically recommended by BimmerLink and have been using it to help troubleshoot our issues.

On or around 7/17/23 I was driving it, and it went into limp mode. I was able to limp it back to a parking lot and call a tow truck. From that experience and the codes read, we replaced the low-pressure fuel pump and fuel filter underneath the back seat. We also did a full oil change and replaced the spark plugs with iridium ones. The fuel filter and the gas in the bucket it sat in was black. Put the car back together, and that seemed to fix it. Fast forward a week later, and it does the same thing. I brought it home and read more codes. It showed low fuel rail pressure. I came on here and did more research.

Yesterday we replaced the HPFP, VANOS sensor, fuel rail pressure sensor, and fuel line from HPFP to the fuel rail, and we sent the fuse box out and had the fuel relay switch replaced. We followed procedures to prime everything and started it. It ran in fits and spurts. Check engine light came on. Ran the code reader, and it came back P0001. The husband drove it around the block 3 times. It was idling super rough. He went back through all the electrical connections to make sure they were plugged in right. He did find one that wasn't quite seated all the way. Went to turn the car over, and now all it will do is sit and try and start, but the motor will not catch. It's like it's not getting any fuel at all now.

We are at our wit's end. We've dumped $1000 into this thing, and it's sat more than we've been able to drive it. Does anyone have any suggestions other than blowing it up?

 

where did you get the HPFP? If you bought it online (ebay, amazon, etc), then that could be your problem. ECS offers a HPFP for around $650 (Mini brand HPFP is $1K+). The HPFP from ebay or amazon are junk (~$150-$200).
When the fuel filter was replaced, did they replace the 3 O-rings inside the fuel filter housing? I've seen people not replace those and it won't hold fuel pressure.
Does your scanner give real-time fuel rail pressure? If so, what psi does it say?

 

We found a guy that is in Canada that rebuilds them. We bought it from him. He has excellent reviews online. With everything else we have replaced, we weren't even sure that the HPFP was the culprit. We bought a non-OEM fuel pressure sensor and VANOS from ECS. They were awesome and verified that the ones we purchased were right.

 

Also wanted to add that we removed the fuel rail sensor just now to check it and hardly any gas came out. Last time we removed it a lot of gas came out.

 

I have never had luck with any rebuilt HPFP. I've tried multiple over the last few years and everyone was junk. I popped the one in from ECS and it fired right up. I have used the ECS fuel pump about 5 times and everyone worked perfectly. It's pricey, but cheaper than the Mini Brand HPFP.

You have fuel at the quick-connect fuel line going into the HPFP, but no fuel in the fuel rail. Well, between those two is the HPFP.

 

We took off the new sensor on the fuel rail and put the old one back on. It seems to have solved the issue. Time will tell. We are in California, and our tropical storm is here with a vengeance. Threw in an earthquake to make things even more fun.

Thank you so very much for taking the time to help with this. I don't know what we would do without this forum.

 

The great hurriquake of 2023.