Arrrrrrrrgh! Intermittent dead 90q ignition (long)

[Huw Powell]

> So, am I right to assume that if a contact in the FPR goes bad, that it will
> disable ignition?  The relay is double or triple throw?  The car doesn't feel
> like it's running out of gas/losing fuel, but more like it's just losing spark.
>  It doesn't always sputter, the tach just rapidly drops to zero, and the car
> won't fire for a few minutes.

No, it's more the other way around.  The only ignition/fuel pump
interface is a tach wire running to the fuel pump relay, which provides
the safety feature of shutting off the fuel pump if the rpm's go to zero
or the red line.

If your car's demise is truly to losing spark (tach caves to zero as
first symptom) then you need to took at ignition components.  The most
likely culprit is at the hall sender on the side of the distributor.
It's three little wires inside the dist. are prone to damage, wiggling
the hall connector thing can be a short term cure.

The best way to test this is to swap in a known good dist assembly, I
guess.

Another place the ignition can die is the power source, to the control
module say, or the coil.  That could be ignition switch related I guess,
or water damage to the ignition control module.

--
Huw Powell

http://www.humanspeakers.com/

http://www.humanthoughts.org/