Highly unlikely this is your problem.  When these go bad, witch
I've only seen one after thousand of vanagon repairs,  it just quit.
Rotor would have nothing to do with it, unless there is some mechanical
issue.
                                                     Joe. W

Geza Polony wrote:

>The Conflict: Lately, the idle on my 84 1.9 has been dropping down to almost
>zero, then back up, then to 250 or so, then back up. I've checked and
>repaired all the engine systems extensively, except for the Hall sender (I
>can't figure out a way to turn the crankshaft by myself.) Everything checks
>out, including coil, all ECU pins, new grounds everywhere, new O2 sensor,
>new Temp 2 sensor, rebuilt AFM, AAR, fuel pressure regulator and pump and
>filter and gas lines...all good...
>
>The question: Could this intermittent idle problem be caused by the Hall sender?
>
>The clue: About three months ago, I replaced the rotor with one NOT coded
>for Hall sensor vehicles, as I wasn't aware there was a difference. (The
>rotor is to Bentley specs ohm-wise.) Could the wrong rotor take out a Hall
>sender?
>
>The red herring? Also, maybe unrelated, the van suddenly started running on
>three cylinders; a voltage check at the #1 injector indicated a bad ECU;
>swapped out and it runs ok again. Could the bad rotor (if it is bad) kill an
>otherwise good ECU?
>
>Thanks for any ideas on this one. I'm not driving the van until this is
>fixed as I don't want to disturb anything else in the ignition system, like
>blow my good ECU...
>
>
>