No start after injectors removal 2012 35D

[sgrice]

Not trying to be annoying, but did you use a fuel line socket and torque wrench?

[3BEP6]

Originally Posted by sgrice

Not trying to be annoying, but did you use a fuel line socket and torque wrench?

Not at all, I’ll crack the #14 open and crank it to see if any fuel come out and until ten and retorque the lines to spec I did it by hand before. Do you know the factory specs?

So if I crack the metal feed line open and see no fuel after few cranks it’s the pump? Is there a way to resistance test it on the prongs?

[sgrice]

23 NM (17 ft-lb).

And this is an Amazon link to the fuel socket kit I used.

You only need the 17 mm socket, but I'm a sucker for adding tools to the tool box.

FYI - here is a link to a forum posting that had a lot of good information on the task. It's for a 335D, but the engine (M57) is very similar. Some differences in the engine bay, but no difference with the fuel injectors themselves. Posts 22, 38, and 39 will sound famiiar to you. If nothing else, it's nice to know you're not alone!

The fuel line socket is a big help - too much torque and you may cut off fuel. Too little torque and you have a leak and can't sustain pressure. As noted in post 39 - a quarter turn can make the difference.

No idea about how to check the hpfp. However, I have seen so many discussion points about the difficulty of cranking after injector replacement, with eventual success after lengthy bleeding efforts, that I am still >90% confident that is your problem. Trying to nail down how to do that properly delayed my working on the valve cover replacement for at least 6 months. Even being really anal about bleeding and torquing I was still very nervous when it came time to start the engine. In my case, fortunately, it wasn't a big deal.

Good luck.

[3BEP6]

I was looking at the diagrams and there’s also a flow control valve on the back of the hpfp and pressure control valve on the rail, since there’s no fuel past the pump, how plausible would it be that the flow control valve on the back of the pump is bad? Or pressure control valve on the rail..

[3BEP6]

Again the only code I have is 4B90 rail control pressure monitoring at engine start.

[sgrice]

My money is still on air and/or connector torque issues. The modern diesels require such high pressures that very small leaks will reduce pressure to the point where there's no ignition.

Assuming you never touched the metal fuel line end that actually connects to the hpfp, I would revert again to loosening the #14 nut on the fuel accumulator. Bleeding/cranking should get fuel bubbling around the threads - though as I recall it did take a total of 30-40 seconds of cranking before getting the air out and fuel coming out. Then you'll want to make sure all of the other twelve connectors are torqued correctly. And then (in my case at least) it will take another 30 seconds or so total cranking time before it starts.

Only after doing the above would I start delving into other aspects of the system.

[Mistercamp]

Check these two connectors, reseat both. Make sure fuel connections are tight. I used a ground down 17 mm, no fancy tools. Run the referenced ISTA test as many times as necessary. I think I cranked for a good 30 minutes. You will get it started. Positive thinking doesn't hurt either. Good luck.

[Mistercamp]

Also reseat fuel sensor on the back of the rail.