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Re: More on TQC HP


>3) Bypass fuel pump relay cutoff. I did this right at the relay (many
>thanks to list members helping find the damn thing) I put in switched 12V
>to pin 87 (I think) of the relay. This makes the pump go on with the key.
>Again, use caution, it means in case of accident etc etc etc...

A somewhat safer way to bypass the relay is to add a new separate relay
across the original, driven by the feed to the alternator idiot light.
This feed is only hot when the engine is running, so that when starting or
following an accident, the ECU is still in control.  The idiot light feed
is separated from the battery by diodes so it is only hot when the engine
is turning.

   alt wng lt  <___     ____> to contact of existing relay
                   |    |
                   |    |
                   /    X
                   |    |
                ___|    |___> to contact of existing relay
          gnd __|__

I had this installed for several years to get around a 4000 rpm cutoff (now
fixed thanks to this list) with no harm to the alternator.

>Will keep you posted, and I welcome all suggestions/warnings.

Sounds as if you're having fun.

Richard Funnell,
San Jose, California
'83 urQ
'87 560 SL