BMW e12 530i FI dle and running progress

[gofast at ix.netcom.com]

Hi everyone - just want to thank everyone again for all the help I've gotten 
in debugging my L-jet fuel injection over the past 2 months. To recap, it 
'chokes' at high rpms. I had kind of concluded that I needed more fuel + 
more timing advance.

I getting to the bottom of this, slowly. It appears that my cars had/has 
multiple problems that have compounded each other. Last night, in one fell 
swoop, I resolved a number of them:

1) A few months ago, I had picked up a bad tank of gas. I had changed the 
fuel filter at the time. Well, last week, I let the fuel level get low, and 
did it choke! Changed fuel filter - ran better, but still 'choked'. Tried to 
siphon out tank to clean out bottom dirt, with not much luck - will try this 
again later.

2) I was in the UK last week. Picked up a euro 630i distributer - much 
better advance curve than stock. Put it on last night, and reinstalled 
Allison optical electronic trigger. Result: better acceleration, better idle 
(can bring it down to 1000 rpm), no more choking, but still has a slight 
hesitation around 4k rpm during *hard* acceleration, after which it picks up 
again.

Todd - no more need to go the MSD route with electronic advance, I think.

3) Checked the AFM flapper - felt like it might stick. Put on another AFM I 
have, a 'new' Python rebuilt unit. Result - low power, but no sticking.

3a) Loosened spring on Python AFM by 3 notches. Result: some more power, 
better sounding engine.

4) This morning, I drove the car cold. It runs *much* better when cold than 
when hot - much more power. Once warmed, it does not have as much high rpm 
torque. I think this is cause it runs richer when cold - I still think more 
high rpm fuel, while not needed, will make me enjoy the car more.

Next step: I am planning to build a DIY o2 sensor led meter, and put an o2 
sensor in the manifold. The 530i has this useless 'seat belt/service' 
warning light thing sticking out in the center of the dash, that would be 
well utilised by sticking a row of leds in there! 

Once this is done, I will try and get more fuel at higher rpms. 
Possibilities are:
a) mechanical: fuel pressure regulator
b) electronic: change resistor's in the computer to give more fuel at higher 
rpms. (Does anyone have circuit diagrams for L-jet ECUs?)
c) electronic: change to euro 635 computer.

Thanks again for all the help. 

Samir Shah
gofast at ix.netcom.com
Stamford, CT