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Re: 76 530i misfire($#%@*! gremlins)bmw-digest V5 #144

Hi Matt

you wrote:

>I just replaced the points and rotor in my 76 530i.  After I got
>the distributor reassembled, I started it up.  First thin I noticed was
>the engine was idleing at nearly 2000 rpm's (normally it idles about
>900)  I took it for a five minute drive thinking the electronics might
>reset.  No luck there.  The engine bucks and misfires in the low rpm's
>gets a little beter about 2500 to 3000 Then goes crazy bucking and
>misfireing.  The 76 has the j electronic injection system, and a
>standard distributer. 

When I rebuilt my 2.5 with K-Jetronic I had a similar problem,  which drove
me nuts for days,  until I finally discovered the problem.  The electical
connection to the distributor has two terminals,  and the system is polarity
dependent.  Although the connector has is keyed to fit in the correct
direction, it is possible to connect it reversed.  When you time the engine
by rotating the distributor body,  you get it running nearly right.  However
because the spark is coming at the wrong end of the pulse,  the distributor
rotor points are almost half way to the next firing position.  When you rev
up,  the advance moves it into the next position,  and all your cylinders
fire out of phase.

Your problem sounds very similar.  Check out you distributor connector for
coorect direction,  retime the distributor body,  and I hope your engine
will run as sweet as mine does.

Best wishes

Sean Murray
Wexford
Ireland