'87 5KCSTQ reluctant to start cold

cobram at juno.com cobram at juno.com
Thu Jan 8 10:09:14 PST 2015

I had a similar thing happen on the 200TQA many moons ago.  After much
diagnosis and shotgunning, it turned out to be the fuel return valve at
the fuel pump was a bit loose or defective and would lose pressure when
the car sat.  

I found a copy of my old post about this:

"When the return valve was loose, it took a whole lot more than 5 seconds
to start, and wouldn't start at all depending on whether the engine was
up to operating temperature or not.  That one was a btch to figure out,
since the valve was failing intermittently, and would test fine.  
Check valve is something everyone should keep as a spare when you change
fuel pumps (usually get a new one with fuel pump), I think it was around
$35 as a separate item, and if you have one on hand, it's probably faster
to just change for a known good one than to test it."

Experience is the name everyone gives to their mistakes

John Larson <viejoloco at comcast.net> writes:

>Cold meaning "sitting until the engine is at ambient 
> temperature".  To answer another post, the fuel pump runs when the 
> car 
> is in a cranking situation.  Fuel pressures appear to be normal.  
> I'll 
> confirm that this morning.  Temps here are currently about 60 
> degrees.

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