E21 wiring harness and connectors, identification help

[YoungSensei]

So a little background, I bought this 1980 BMW 320i from a guy who couldn't get it to run. In his attempts to get it running, he disassembled a majority of the fuel injection system, as well as the engine harness connectors + sensors. Now I'm the lucky guy that gets to put it together.

I think I'm doing a fairly decent job, luckily I have another 320i 10 ft away from me that I can compare w/ as well as the factory manual and BOSCH fuel injection manual. But I'm struggling to figure out where these Dark Brown, Black, and Blue connectors go to. They seem to originate from a Relay/Block on the firewall, but my other 320i doesn't seem to have this. I originally thought these plugs went to the enrichment injector, the thermostat housing, and the addt. air slide close to the center of the valve cover. But I already have another bundle of wires that would seem to make more sense going to those components. Also there is a black and yellow wire w/ spade connector, and then additional splice of black and yellow wire that I'm not really sure goes to, although I read that it goes to the starter. I have it plugged in, but then none of the other connectors really reach. So i'm confused. Any clarification would really help. Thanks!

https://youtube.com/shorts/b6sOvAYMfWk

https://youtube.com/shorts/qE5llVaGlkk

https://youtube.com/shorts/KnPqnauJIB8


IMG_4109.jpg

[amarino]

The videos are private and unable to view them.

The extra relays and wiring are the "drivability kit" that was added to some. Some info and pics here: https://www.bimmerforums.com/forum/s...0#post24071460

The DIY / FAQ thread has some info on resetting the base mixture and hopefully that will allow you to get it started.
https://www.bimmerforums.com/forum/s...7#post15904137

Also this is a good book to help troubleshoot if you need it:
https://drive.google.com/file/d/1jOK...ew?usp=sharing

[YoungSensei]

I have updated the videos, should be available for viewing now. Thank you for the information. Reading about the "drivability kit" now...

[amarino]

It's probably best to just remove it, but keep it all intact and don't cut any wires to save it.

Then get everything back together using the regular wiring harness.

[YoungSensei]

Sounds good. The thread about the drivability kit has been very helpful. I believe I have all connectors identified now, as well as some missing parts. Have placed an order for all hoses + t connecter that goes to the barb fitting on the intake boot, left and right side. Had to order an additional air slide valve as well as the fuel line to the enrichment injector, and the fuel line to the bottom wur port. Once I get those parts, I think i'll be ready to button everything up and start cranking.

One thing I havent ordered yet was the hoses for the charcoal canister. It seems that both of them are missing. I think one is supposed to run along the front of the car and then down the passenger side, and one runs down the driver side, although I'm not certain. Am I going to have any issues starting the vehicle without these lines?

[amarino]

Sorry I haven't had to mess with or think about those lines on my car. Maybe someone else can chime in.

[tbeach54]

Greetings all,
I am at about the same place with my project. I have got the engine to turn over, for the first time in 32 years, but have no sound coming from either fuel pump. New pumps, etc so I'm thinking it has to do with the fact that I do not have the relays that go on the firewall. Where can I get them? I tried to get numbers off of them on the driveability thread, but no dice. All this info is very helpful to me and I'm sure others. Thanks to ALL!!

[Jacm2015]

Greetings all,
I am at about the same place with my project. I have got the engine to turn over, for the first time in 32 years, but have no sound coming from either fuel pump. New pumps, etc so I'm thinking it has to do with the fact that I do not have the relays that go on the firewall. Where can I get them? I tried to get numbers off of them on the driveability thread, but no dice. All this info is very helpful to me and I'm sure others. Thanks to ALL!!

Here’s my fuse box that show the part numbers for my relays, however my car is a carb’d 316 so not sure much help this will be.

If you do know the position that the relay is supposed to be in when it’s active you can try jumping it by using a safety pin or something. Sorry I couldn’t be of more help.
-Cas

[mjweimer]

One thing I havent ordered yet was the hoses for the charcoal canister. It seems that both of them are missing. I think one is supposed to run along the front of the car and then down the passenger side, and one runs down the driver side, although I'm not certain. Am I going to have any issues starting the vehicle without these lines?

You should not have an issue starting the car without the hoses as long as the tank is still vented to atmosphere and the connection at the throttle body has been plugged (big potential vacuum leak).

Here is a picture of my charcoal can:



Sketched red line is from the tank vent to the charcoal can. Green line is from the can to the connection on the throttle body.

This is the connection at the throttle body:



This is simply routed out from the charcoal can, under the airbox and then up the side of the engine (to the right of the air meter boot). The connection is under the cold start injector on the base of the throttle body.


A bit closer look at the connection of the hose to the vent line from the tank:




This metal line runs from the top of the tank, along the bottom-right floor pan, eventually transitions to the side of the right front frame rail and then turns under the frame rail to cross over on the inside of the lower front valence. The rubber hoses are 6mm ID x 11mm OD. Easily sourced from BMW or in the aftermarket from Continental (CRP).

Greetings all,
I am at about the same place with my project. I have got the engine to turn over, for the first time in 32 years, but have no sound coming from either fuel pump. New pumps, etc so I'm thinking it has to do with the fact that I do not have the relays that go on the firewall. Where can I get them? I tried to get numbers off of them on the driveability thread, but no dice. All this info is very helpful to me and I'm sure others. Thanks to ALL!!

The fuel pump relay is connected to the side of the fuse box in its own holder. The relay circled in red is for the fuel pumps/fuel control system, the relay circled in green is for the Lambda control/Oxygen sensor circuit.




The firewall relays referenced in the driveability thread do not have any control of the fuel pumps. You can manually run the fuel pumps to test by jumping the relay - see "jumpering the fuel pump" in post #6 of the thread below (about halfway down the post).

https://www.bimmerforums.com/forum/s...7#post15904137


<Edit for future search reference>: The fuel pump relay is BMW p/n 12 63 1 277 245, it is manufactured by Kaehler and had until recently been readily available as an aftermarket item for ~$25. Unfortunately, it seems that these are "backordered" through all the usual places leaving only the OE part through the dealer at ~$175 (!!)

[GDAus]

Hi ..

You can jumper the fuel pump this way, but you need to have the ignition switch in the run position.

An alternative method for testing purposes is to connect Battery 12 +ve (positive) to connector socket 87 ... that will run the the pump(s) directly without turning on the ignition.

Cheers

[tbeach54]

Sooooooo....
I jumpered the fuel pump(s) and they seem to work fine.. I put the relay in and nothing! Two different relays. One new and one not so new....hmmmm...??
Any ideas?
Seriously, thanks, everyone for your input!!

[YoungSensei]

Sooooooo....
I jumpered the fuel pump(s) and they seem to work fine.. I put the relay in and nothing! Two different relays. One new and one not so new....hmmmm...??
Any ideas?
Seriously, thanks, everyone for your input!!

Can you post a picture of the relay?

Im at the stage of cranking and trying to get the car to start as well. I'm noticing excessive fuel being delivered to the injectors with the pump relay jumpered and key in 1 position (very loud and audible fuel injector noise/squeel). Tried to adjust the 3mm mixture screw, and it doesn't seem to be effecting my injectors in any way. Maybe my fuel distributor plunger is stuck in the up position? I verified I have spark, and I obviously have fuel to injectors, although I think I have way too much of it, causing the engine to flood. Also, a ton of fuel is leaking from the mating surface of the distributor when doing this test. So much so, that I can clearly see a waterfall of fuel going down the driver-front side of the engine.

[YoungSensei]

Oh and I dont think you'll hear the fuel pump running until you actually start CRANKING, with the relay in. With the relay jumped, the fuel pumps will run with key in 1 position, that's why jumpering the relay is so helpful for testing.

[YoungSensei]

So I pulled the distributor off by undoing the 3 flat head screws. I was able to gain enough clearance to stick my finger inside and feel the top of lever-plunger bearing/riding surface. While touching this surface, and adjusting the 3mm screw, I can feel it moving up and down I believe. I also was able to feel the plunger moving freely inside the distributor. So i'm kind of stuck now. For some reason my fuel injectors deliver enough fuel that I can audibly hear them squealing, yet I do not know why. I believe they are delivering too much fuel, and that's the reason I'm having trouble getting the vehicle to start.

[tbeach54]

Thanks! I eventually figured out that was the case with the relay in position. Just took me a while. Actually installed a new fuel line to the distributor as was mentioned in another thread. Ready to try fuel when I get a chance....SOON!

[YoungSensei]

Hopefully might get some direction on what my issue may be. I'm currently reading over the Bosch Fuel Injection and Engine Management book again to see if I can figure out why my injectors are delivering fuel without the air meter being lifted (while fuel pump relay jumpered).

[GDAus]

Hopefully might get some direction on what my issue may be. I'm currently reading over the Bosch Fuel Injection and Engine Management book again to see if I can figure out why my injectors are delivering fuel without the air meter being lifted (while fuel pump relay jumpered).

Hi ... just doing a post for you in your other thread ... it is a bit long, should have it finished shortly.