Ford: 1989 Crown Victoria: Replaced fuel pump, died shortly afterwards

Hi,

My grandparents had a 1989 LTD Crown Victoria with the 5.0L fuel-injected
engine. It wasn't running, and after a little troubleshooting, I found that
the fuel pump was frozen. I removed the fuel tank and the pump and -- after
seeing a fair amount of rust present -- wasn't surprised that the pump had
died (how much rust is there supposed to be in a gas tank?). I bought a new
pump and was initially surprised to see that it was noticeably smaller than
the original, but the guy at the store assured me it was the correct model
and just that pumps have become more efficient over the years, hence the
reduction in size. (The pump came with a new rubber noise damper so that
the new pump would fit the original bracket.)

Anyway, I installed the pump, cranked the engine and -- hooray! -- it turned
over and started. We took it around town for a couple of days (probably
about 4-5 starts), and it was fine -- although it did seem to require
excessive cranking to start. Additionally, the new fuel pump would
sometimes make a loud, high pitched whine after running for awhile (15
minutes?) -- noticeably louder than the last fuel pump ever did (when it
worked). Finally, we were leaving a store and _no_ amount of cranking would
start the engine. It doesn't even try -- you can hear one singular "pop"
indicating that the engine is getting a little fuel, but after that it seems
as if there's almost no fuel being delivered to the injectors.

I didn't have a fuel pressure gauge with me, but I verified that -- while
the fuel pump is running -- fuel does come out of the Schrader valve where
you're supposed to connect your gauge. However, as soon as the fuel pump
stops, there doesn't appear to be any fuel pressure whatsoever. My
understanding (from the Hayne's manual) is that this is wrong -- the fuel
system is supposed to hold pressure. On the other hand, the fuel return
line going into the gas tank just has a small rubber ending on it with a
'slit' opening so... what is supposed to ensure the fuel system returns
pressurized? Is there a check valve somewhere?

My working theory is that the fuel pressure is simply too low to be making
it into the injectors with enough volume to run the engine. That would
explain why the car took excessive cranking to start, although not why it
was working fine for awhile and then suddenly stopped... I would think that
perhaps the fuel pump 'partially' died, becoming weak, but I have a hard
time believing a new pump would do such a thing... but then again, it did
make those loud high-pitched whining noises, so who knows?

Any ideas? The Haynes manual says that if the fuel pressure is low and
there aren't any leaks (there aren't!), you should replace the fuel pump...
but it seems to me the lack of holding pressure might indicate some other
problem? Or should I just replace the fuel pump (again!) and see what
happens? (The fuel pump has a lifetime warranty.) Also: The fuel filter
has ~30k miles on it and -- although you can't see into it -- I could blow
through it, so I wouldn't think it was clogged. (Plus I can't imagine the
fuel filter just suddenly clogging like that.)

Thanks,
---Joel Kolstad

My '84 TBird (with CFI but still high pressure injectors) leaked down within
a minute of turning the engine off. It did it new and was checked with no
problem found. I drove it 180k miles and it's new owner has about 20k more
on it now. Never changed anything in the high pressure part except filter.
Mr. Moats was probably right on about the filter, tho. Plugged filter, no
(or very little) fuel. The regulator is a little round can-thing. Maybe 2"
by 2" and often has a hole in the top where a hex key will fit.

Paul in Dayton


"Joel Kolstad" <Com> wrote in message
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