[Gmecm] Re: Undignified death of a project :P

[Jay Vessels]

Hi there!

Andrew Gibson wrote:
> Low oil shutdown on GM products: Been there for years. Yes I had it
> on the truck. It works by the ECM powering a fuel pump relay on
> initial key on and cranking. Then the oil pressure switch takes over.

There is some tech literature that claims this is how it works, but it 
is not true on any TBI or TPI GM engine I've touched.  It's an easy 
experiment -- unplug the oil pressure switch and start the vehicle.  It 
will keep running.  I proved this to myself on a 1227429 TBI engine.

I'm not sure why GM didn't trust the relay (especially since it added 
cost), but I assume their legal team was involved...

Jay Vessels
1982 Chevrolet S-10 Sport, 2.8V6 TBI
1984 Chevrolet S-10 Blazer Sport, 2.8V6 (TBI pending)