I am doing a piston soak and after she's done soaking, I want to pull the correct relay so I make sure no fuel injection takes place. Here's what I found online.

 

Here's what I found online.

The injector relay is the one labeled as ignition

 

You want to pull fuel pump relay K96, which is located here.

BMW WDS Online

bmw wds online for all browsers

bmwteka.com

 

You can find the wiring diagrams for your MS45.1 here.

BMW WDS Online

bmw wds online for all browsers

bmwteka.com

 

This is all I can find in the Bentley manual, but it only refers to model year 2001:


 

I just did a crank wash and about to do a piston soak with BG EPR. Here's an excerpt from MrMCars write-up.

 

Thanks sapote!!

On a side note, can someone explain this about a piston soak...

When soaking the top of the piston, how does the liquid, in my case BG EPR, not deep down into the bottom end? Dumb question but I genuinely am ignorant in this. And if the liquid stays on top of the piston, couldn't I use my oil extractor and remove the BG EPR after 24 hours instead of doing what MrMCar suggested on cranking the engine to expel the BG EPR?

 

When soaking the top of the piston, how does the liquid, in my case BG EPR, not deep down into the bottom end?

It does, but very slow via the ring gaps/ring lands.

 

I have not done the piston soak, but I have heard people tilting the car up on the right side to make the engine (pistons) vertical, allowing more even distribution of the cleaner.

 

Yes, that's what MrMCar suggested as well.

 

What would happen if I pulled the blue dme relay and tried to start the car?

 

I think what you want is to crank the engine with no fuel. Right?
Most people just pull the fuel pump relay as I suggested above.

 

I think why MrMCar suggested the relay for the injectors is because upon crank, even with the fuel pump relay removed, there will still be pressure in the fuel system and the injectors will squirt like a Los Angeles amateur audition.

 

even with the fuel pump relay removed, there will still be pressure in the fuel system

You purge the fuel pressure using the schrader valve on the fuel rail.

 

there's a relay for the INJECTORS?!

 

According to everything I can find, the fuel injector relay the light green one under the hood, beside the blue dme relay. I'm seeing it sold on eBay and various other places as the fuel injector relay.

My cars currently jacked sky high on the right side enjoying her BG EPR bath. My first notice is how amazingly clean the inside of the oil filter housing looks. It's like factory new shiny inside after running BG EPR through the crank earlier today. I installed fresh oil before I did this and the oil came out definitely discolored and it wasn't in there that long. So I think it is working. Tomorrow I'll get out what's sitting on the pistons and install some liquid moly and see how consumption is. Will be a while considering I only put about 2800 miles a year on her now since I don't travel anymore.

 

Here's one example I found...

Pardon Our Interruption...

 

Also found this.

 

I thought the injectors were engaged directly through the DME. But I forgot that they are "mass-switched" as we say in Dutch, don't know how to translate it correctly. So if the positive side is connected with a relay that could make sence. I'll stfu

 

So I definitely can confirm that pulling the green relay under the hood fuse box will in fact stop the injectors from squirting. I did this tonight to expel and left over engine treatment after my piston soak. She's now ready for some oil and miles!