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Re: O.K., what did I do to this one?

MHLIGGINS wrote:
> 
>      The backup '87 5K CS TQ has joined the primary one in semi-retirement.  I
> was driving on one of the roads at the plant and it stopped running.  Died.
> Right there.  Engine will turn with the started, there is compression this
> time.  When I turn the ignition on, the fuel pump did not cause the warm up
> regulator to click, so I suspected a bad fuel pump.  Changed the pump, still
> no fuel.  Also no spark, which I think is normal if there is no fuel.
>      What sensors have the power to shut off the fuel pump?  I have checked
> pins 1 & 4 at the fuel pump and there is voltage there.  With a weak battery
> it was 9v, have the battery on a charger now.
>      Any suggestions on which sensor(s) to look at?  Any other items that may
> have an impact?  Any loose wires that could do this?
>      All help appreciated.
> 
>      Thanks.
>      --ml
>      Now More Confused in Bucksnort.

	Did you try a new fuel pump relay?  That little gismo has a lot of
responsibility if I am not mistaken ( Frequency valves, cold start,
wastegate solonoid, etc ).  
	Try a engine off diagnostics ( sounds like that is what you are stuck
with ).  If you have a factory manual the instuctions are in there.  If
you have a manual or already know about this, I apologize for going on
about it.  
	Turn the key on ( not cranking ) and bridge the fuel pump relay ( in
fuse box ) with a spare fuse for a least 4-5 seconds and remove it.  The
check engine will flash while you are doing this.  The fuel pump should
start and continue running. You can repeat that procedure, I think 5
times, for other switches that the fuel relay controls.
	
	1.  Fuel pump
	2.  O2 Sensor Frequency Valve
	3.  Wastegate Solonoid
	4.  Cold Start Valve  
	5.  Charcoal Canister valve
	
	When you are all finished all these switches and the fuel pump should
be buzzing, clicking or whatever at the same time.  If any don't replace
the relay.  When finished just turn the key off.

Colin
87 5KCSTQ