[Prev][Next][Index][Thread]

More K-Jet idle problems

Dear Bimmerphiles

I'm still trying to solve the idle problem with my car.  I am pretty sure
that I have isolated the cause to the problem as having to do with the vacuum
advance.  Please help me if you can!!  see below:

To recap, the problem is that the car won't idle between 1500 and 600 rpms
with any consistency.  When I turn the idle screw in, it seems to drop all at
once to a low idle speed.  What it seems like is that once the engine speed
gets below a certain point, the ignition retards and slows the engine down to
an unacceptable idle.

If I disconnect both the advance and retard lines to the ignition
distributor, I'm able to readjust the idle speed to the proper level and get
it to stay there.  However, I'd like it to work properly with the advance
connected.

How can I verify that the advance unit is working properly?  I have put
vacuum on the advance and retard seperately, which results in either an
increase or decrease in engine speed.  Is there a more thorough way of checkin
g this system?

Also, can someone explain the function of this device?  I understand the
advance, but I've never had a car with a vacuum retard.  For example, does
the retard simply retard the timing back to zero advance, or does it actually
retard the timing?

Finally, my car is a 1982 323i, and the advance unit won't likely be available
, except for big $.  I was wondering, do these units interchange between
different Bosch distributors?  For example, might i be able to pull one of
these off of a 320i?

Thanks, in advance, for your help!!

Paul King