Hot Start no spark

[Bernard Littau]

I'd be really suspicious of a flywheel Hall sensor at this point.  Ignition
switch unlikely as it does not see any significant heat or cool during the
failure time.  ECU itself may be an issue, but again, no significant heat or
cool during failure time, so unlikely.

Check the alignment of the dizzy window very carefully.  The Hall sensor
signal does change with increased temperature, so it's possible that the
signal is being altered by heat to the point the ECU no longer finding it
withing the window.  If the dizzy is barely within the alignment window,
this might happen with heat on a good dizzy (or two).  You might try nudging
the dizzy 10 degrees one way and then the other to see if anything changes.

I assume you've tried the no start code pull from the ECU?

Best,

Bernard Littau
Woodinville, WA
'88 5ktq

On 2/3/06, Doyt W. Echelberger <doyt at buckeye-express.com> wrote:
>
> OK, more info on the hot start problem in the 88 5kt automatic.
>
> Tested for spark and fuel when the problem showed its ugly head.  No
> spark.
>
> Doesn't appear to be a fuel problem. This is an intermittent ignition
> problem that happens when the car is turned off hot and allowed to sit for
> a short period of time.
>
> Owner swapped dizzies with good working engine, no change in problem.
>
> Going to check relays and grounds as suggested by list.  Also considering
> ignition switch malfunction a cause. Any ideas here?
>
> Doyt
>
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