Unidentified plugs in Engine Bay plus oil leakage

[Dweed144]

Hi All,
I have recently purchased a 1989 320i with 115k.

So far I have had some serious rough running problems which I think have been resolved with a new intake boot. The old one had perished quite badly. The forum has been hugely helpful in getting me this far.

I've done an oil and filter change, new plugs, new fuel filter so far, and I think I will have to do the timing belt as in the paperwork I have which goes back to 2008 there is no mention of a timing belt replacement.

I have found 3 plugs in the engine bay which aren't attached to anything. I was wondering if someone might be able to shed some light on what I might be missing? The first one pictured is suspiciously close to an empty mounting bracket. This plug is hanging under the intake manifold. The second plug comes out of the wiring loom with the washer fluid plugs. The third plug is just under the fuse box.

Also there quite a lot of oil on the nearside of the engine, it seems to me to be leaking from the oil reservoir leading to the power steering, as the tube has a junction lower down which is oil covered. The only thing is the oil in the reservoir seems to be a thin greyish oil, and the oil in the engine bay seems to be viscous and possibly greenish?! I realise this is a rather vague question, but if it sounds familiar I would be interested in finding the source of the leak.

Plugs:




Oil:

[Cloggy Saint]

The plug in the first picture looks to be part of the emissions control system and would fit under the throttle body on a cat' equipped car. All looms had this plug whether the car had a cat' or not. The empty mounting bracket should have the injector loom fitted in it so I guess that's hanging loose somewhere.

[Dweed144]

Ok thanks for identifying that, although I'm pretty sure that I saw what I assumed was the cat' when I was changing the fuel filter today. Sorry for the stupid question, but the throttle body is the main unit with a plastic lid, before the rubber intake boot, right? It has a plug going into the top of it....
I know I should have a Haynes Manual by now, and then I wouldn't have to bother you with these stupid questions.

[Brianmoooore]

Do you have an OBC in place of an analogue clock? There is a spare plug on the OBC loom near the fusebox, with another one connected to it just the other side of the bulkhead in the cabin. I have never seen it used, and have no idea what it was intended for!
Power steering pipes are notorious for leaking at the connection to the bottle. Cut the old non adjustable clips off, and replace with heavy duty jubilee type clips. (This is so common, it's the third time I've written this in a week!!)
The fluid should be a clear cherry red colour, so it sounds long overdue for a change. You will need to change it at least twice to get all the old fluid out and give the new stuff a chance of staying clean.

[Brianmoooore]

Thing before the rubber boot is the air flow meter, bolted to the air filter housing. The throttle body is at the engine end of the rubber boot, bolted to the inlet manifold.
It would be very unusual for your car to have a cat., but there's an easy way to check. Feel under the battery tray, and you will find yet another unused connector - a round one, with a blanking cap fitted to it. This is the lambda sensor socket, and no lambda sensor, no cat. If there is a plug with a lead connected to it fitted to this connector, then you do have a cat.

[Dweed144]

Indeed I do have an OBC. Thanks for the info on the power steering. I will remedy that as instructed.
Also is 24mpg on combined london traffic and some motorway cruising about normal? I was kind of hoping to find a fuel leak when working on the car today.... I knew they were thirsty but i've done about 180 miles and im down to an 1/8th of a tank. That said, now I've cured the massive air leak maybe things will improve...

[Brianmoooore]

I live a world away from London traffic and the nearest motorway is forty miles away, so I'm not really qualified to answer this question, although I'd say it doesn't mean "there's definitely something wrong" low. From your pics., yours looks like a typical neglected E30 in need of some TLC, so there's probably another couple of MPG to come.
There's a very strange looking lump in your oil leak pic, right above the engine mounting arm bolts, that shouldn't be there. Could this be the missing injector loom plug and socket that has been removed and the wires permanently joined together?

[Dweed144]

Yes. I just googled the injector loom plug and I definitely haven't seen that anywhere in the engine bay! That did lead up into the darker recesses under the intake manifold so I assume you are right.
What would you recommend as a course of action in terms of the TLC required. Obviously that's difficult not knowing whats wrong, but given your experience what would your stage 1 list of repairs, renewals, and checks be??
So far i've done some of the basics, but I'm coming to this from a carbureted 4 cylinder 1971 Volvo 144 which is somewhat less complex.

[BenHar]

Do you have an OBC in place of an analogue clock? There is a spare plug on the OBC loom near the fusebox, with another one connected to it just the other side of the bulkhead in the cabin. I have never seen it used, and have no idea what it was intended for!

The plug on the OBC loom by the fuse box is for a limit switch on the bonnet runner if there is a BMW magnetic key alarm fitted.

The OBC ECU will be a blue box in this case.

Ben

[Brianmoooore]

What's the colour of the wires to the plug near the fusebox?
TLC: One of the first things to find out is when the cambelt was last changed. If no history is forthcoming, then a new belt, tensioner pulley and water pump should be close to the top of the list.
If the steering fluid has been neglected, then there's clutch fluid, brake fluid and coolant changes to consider.
Engine wise, eliminating all air leaks on the inlet side, checking the operation and adjustment of the throttle position switch, and investing £66 into having the injectors rebuilt (see our traders' section), will be a good start.

[Dweed144]

The wires are Brown and Brown with a green stripe.
Thanks for the list. I will get on with that and see how I go.