dml@bleazard.net wrote:
> In article <f0ohjp$nk5$1@bent.twistedbits.net>, SilverEightynine@aol.com
> (Terrible Tom) writes:
>>
>> Now I don't know for positive (maybe bernd can chime in on this one) but
>> that splice issue, could very well make the truck act like a dead fuel
>> pump. I think the ECM needs to get power in order for the fuel pump
>> relays to switch over and pressurize. It would be a good idea to see if
>> you are getting power to the ECM before you do anything else.
> If it gives me the 55 "end of test" code, is it safe to assume that the ECM is
> getting all the power it needs? I guess it's possible that there's a wiring
> issue that only cuts the power supply to the fuel pump. No matter what, I'll
> check the voltage right at the top of the pump itself before pulling the old
> one. 12V + no fuel = bad pump.
I don't know if it means its getting all the power it needs, but it
would seem its got enough power to function; i.e. its probably not a
fried PCM, so for now, I would work under the assumption that it is
OK.
Based on the symptoms you described, I would be inclined to lean
towards a failing fuel pump, or at least some sort of restriction
preventing fuel from getting to the engine. I would tend to think it
may not be the splice just because of the degrading symptoms that seem
to indicate a lack of fuel combined with a lack of failure of other
components such as the PCM. As I recall, if the spice is to blame,
then while the fuel pump is without power, the PCM itself should be
without power as well. I know the '95 has a returnless fuel system,
but I don't recall when Dodge eliminated the in-line fuel filter. I
have a feeling you don't have one, but if you do, check it out to make
sure its not plugged.
Something that might help to determine wether it is the splice or
the pump itself is to pull the fuel pump relay in the PDC and check
for power there. If the truck is not starting and you see power at
the fuel pump relay, then chances are the problem is not the splice.
(True, the splice could be just barely making contact - enough to get
a reading on a multimeter, but not enough to actually pull any amps,
but you've got to start somewhere.) :-) (While you are fiddling with
the relays, you probably have a relay which is identical to the fuel
pump relay in the PDC powering something else - swap them to eliminate
the relay itself as a suspect. See if you can hear the hum of the
pump when you turn the key on. Assuming you've got power at the fuel
pump relay, and you can't hear the pump humming, the best assumption
would be that the pump itself is bad or there is a problem with the
electrical circuit between the relay and the pump. You might end up
having to move the bed after all if you want to check out the
situation there. (Especially with a full tank of gas thrown into the
equation.) You can probably just loosen the bolts on one side and
remove them on the fuel tank side, which may allow you to tilt the bed
up enough to give you some working room in there, and avoid having to
remove the bed entirely.
Another test you may be able to do prior to having to deal with
the bed is to check the resistance between ground and the power feed
to the fuel pump at the relay socket. Check your FSM for the wiring
diagram to see if this is worthwhile; I don't know if the fuel pump
has its own ground or uses chassis ground, but it seems like if you
check the resistance between ground and the fuel pump power feed, it
should be something less than open/infinity. If you don't see any
continuity there, the problem may be a loose connection or broken wire
preventing power from getting to the pump or preventing the pump from
getting a proper ground. Its late and I haven't thought that through
very well so someone might want to chime in if I am off base here, but
just thought that might be an easy test to do in order to determine
wether the truck can "see" the fuel pump before taking the step of
actually unbolting the bed to get to the pump itself.)
BTW, I know you were planning to head down here in a little bit to
do some tune-up work, I'd be glad to help you chase this down or
replace the pump, etc. but of course the catch is its a bit hard to
drive down without a working fuel system. :-) If you were to rent a
dolly, Norah's dak could easily handle towing the '95, and if the
problem turned out to be something more, you would have the option of
leaving it here temporarily since you'd still have a ride home. The
other option would be to load it in my trailer behind the 3500, but I
am relatively certain that a U-haul dolly would be cheaper than the
cost of diesel to pull the trailer up to Toronto and back, and of
course that option does not leave you with a spare vehicle to get back
home in case the '95 has to stay under the knife a bit longer. I'm
not sure what you were planning as far as fixing it goes, so I just
thought I'd do some thinking out loud. :-)
At any rate, good luck with it, and let me know if I can be of any
help! (Hmmm, if I didn't know better, I might have suspected that
your Dak was reading over your shoulder during the "Beater Economics"
thread!) ;-)
--
-Jon-
.- Jon Steiger -- jon@dakota-truck.net or jon@jonsteiger.com -.
| '96 Kolb Firefly, '96 Suzuki Intruder, Miscellaneous Mopars |
`-------------------------------- http://www.jonsteiger.com --'
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