thanks Stuart,

We thought that we reversed the wires ... but no... if the pair of wires in
the large white plastic connector (at the 2 prongs post) are reversed, the
van cranks but won't start. Reversing the 2 black wires at the 3 prongs
post doesn't do anything.
The same connection on the old ignition coil makes the tachometer work
again.... I scratch my head....  :-)

On Mon, Aug 30, 2021 at 9:47 AM <stuartmacm@gmail.com> wrote:

> Are you sure you didn't reverse the wires?  There are + and - terminals on
> the coil.  There is nothing in the coil that runs the tach, it just counts
> the on off pulses that fire the coil.
>
> Stuart
>
> -----Original Message-----
> From: Vanagon Mailing List <vanagon@gerry.vanagon.com> On Behalf Of Dan N
> Sent: Monday, August 30, 2021 9:31 AM
> To: vanagon@GERRY.VANAGON.COM
> Subject: New iginition coil behavior
>
> hi all,
>
> My son's 1988 GL doesn't run well (lack of power, lack of response)
> despite a full tuneup (spark plugs, dist cap and rotor, fuel pressure
> regulator, checking the TPS etc etc.) The mechanic suggested a new set of
> spark plug cables. We put a new set of spark plug cables and a new *out of
> the box* Bosch ignition coil. (the old one is age unknown in back color,
> could be an original one)
>
> It's running way better but the tachometer doesn't work anymore. We check
> the connectors many times but it still is not working. So we swapped back
> the old ignition coil and the tachometer worked again.
>
> So my questions are:
> - will the new ignition coil fail soon too?
> - Is the portion that feeds the tachometer independent from the main
> function of the ignition coil (feeding the distributor)?
> - and could we leave it in and use the van while waiting for another one?
> thanks
>
> dan
>
>