RE: 1986 325e questions

["Fadeev, Alex" <Alex.Fadeev@xxxxxxxxxxxxxx>]

> I remember in my 911SC, when the "low fuel" light came on it 
> meant that I was on reserve, which meant about 2.2 gallons
> of gas or something left. I've looked all over the manual
> for my e30 and I can't find any indication of how much gas
> is left.  Does anyone know?

I believe the reserve light should come on with about 5.5L left. That's
about 1.5 gallons.
Just after mine lights up ('89 325i) I can put in about 14.2 gallons. This
at most adds up to under 16 gallon or under 60 liters full tank. BMW claims
my car should have 64 Litters (14.1 gal) tank. I still haven't figured that
one out.

> If I had the on board computer, that'd tell me miles left and
> stuff, right?

Yes, with varying degrees of INaccuracy. 
BMW makes absolutely no claims about OBC accuracy. It's mostly a toy.
Even if you retrofit an OBC, don't rely on it too much. There was a recent
post here (or was that on UUC digest?) about a shmuck who wanted to sue BMW
for an OBC that told him he could drive 15 some miles to his favorite gas
station in a lousy part of town...

> Can I just swap the OBC for my clock/temperature unit?
> Will it plug in and work?

Absolutely.
OBC is a fun toy and retrofitting one is a pretty satisfying upgrade.
You will need:
- - OBC display with "3 12 TYP" coding plug. You can buy an OBC from any other
E30. Just make sure it has your coding plug (or set aside ~$40 for a
replacement plug from a dealer). 
- - OBC harness. This one replaces the instrument cluster (blue plug) ->
mini-OBC (green?) plug. Also has plugs for the temperature sensor and CODE
interface wires that plug into 'main' harness (near the DME in the glove
box). 
Optional goodies:
- - OBC enabled turn signal switch that also supports 'push-in' OBC mode
cycling
- - coding 'relay' box (mounts on the firewall next to anti-lock
computer/steering column). This one supports the 'CODE' functionality by
sending 'do not fire injectors' command to DME (thus the harness connector)
after 3 failed attempts to enter correct code into the OBC.
- - extra horn

I did this a few years ago and would do it again.
Feel free to drop me a line off-line for details.

> Also, has anyone converted to a power sunroof from the manual 
> crank?  Is it just swapping in the motor, relay, a bit of wiring,
> and a gear, or are the two systems completely different in other 
> ways as well?

You would need a power sunroof cartridge + switch. 
Best obtained from a junk yard.

have fun,
alex f

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