Weird MC engine problem

Phil Payne quattro at
Fri Aug 9 22:08:56 EDT 2002

> By "appreciable load" do you mean just revving the engine or actually
> driving?

Stationary it will rev to the limit very cleanly.  No hesitation, no misfire, all instruments

Put it in gear and do a traffic light start - it dies in two car lengths.  Death is not as
immediate as fuel pump cutoff, but quite similar.  The fuel pump cuts after the usual two
seconds of no revs.  Control and system pressure stay nominal throughout.

> Another thought, fuel related:  Sticky plunger in the metering head?  Idles
> Ok but when you give it throttle it can't compensate with more fuel and
> dies? Maybe actuates too slowly, engine dies then gets too much fuel when
> you try to restart?

It revs _very_ well when stationary.  Haven't swapped the metering head yet.

> On the electrical side, is the hall sender providing a clean signal? Maybe
> as the distributor spins faster the signal is too dirty to provide a good
> pulse and the ignition gets confused.  Of course that would (should) show up
> when pulling codes.

The MAC14 only uses the Hall sender during the start sequence.

> Alternator not up to snuff?  Battery going bad ie. creating a short under
> load?

The alternator is not the right one for the car.  Voltages _are_ a bit low.

> Of course your, and my, favorite... check the grounds. I know, preaching to
> the choir ;^)

I haven't done that yet.  It's on the list.

  Phil Payne
  +44 7785 302 803
  +49 173 6242039

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