"Jim Warman" > wrote in message news:<xXTmd.183833$9b.6178@edtnps84>...
> Rather than close the injectors, the PCM opens them (they are normally
> closed). Depending on the program strategy, the PCM *may* pulse all the
> injectors once when the key is turned to run or start to purge air or
> vapours from the fuel rail and/or richen the mixture in the intake port.
> Again, depending on program stategy, the PCM may bank fire sequential
> injectors until the PCM sees the motor is running or until a predetermined
> time period or temperature is reached.
>
> Whether the fuel rail pressurizes or not, the fuel pump should only run
> (KOEO) for 1.5 to 2 seconds (gasoline engines) and wont turn on again until
> the PCM sees an rpm signal. If your pump is running continuously KOEO, then
> there is a problem with relay, wiring or PCM (the relay control circuit is
> ground side switched by the PCM). You'll need to do some circuit testing
> while the problem is happening. It makes no sense to throw parts at this
> thing willy-nilly without some kind of diagnostic proof of a problem.

Ya I know about throwing money at car problems.
But at this point, it does seem like the ECM or PCM (the one that
controls the injector pulses) is mal-functioning. I can get it to stop
just by waiting, or by switching the key on - off (no engine cranking)
Or after its running & has gone into a "check engine light" condition
& poor throttle response, turn the engine off & restart - no check
engine light & great throttle respose - for about 1-5 minutes!
Evertime.
PCM or ECM?? the one behind the passenger side headlight.
Carquest says there were 4 or 5 to choose from, depending on which one
I had.
great! $140.

I think I'm just gonna do it this weekend.


Gil


-
>
>
> "Gil" > wrote in message
> m...
> > All well & good.
> > Q: Does the ECM tell all the injectors to close when first turning on
> > key? Thus allowing fuel rail pressuraztion. if a couple aint closed
> > due to ECM mis control, bingo no pressure.
> > Then after crankshaft revolution (crank sensor) start pulsing??
> > Could this posibly be the culprit? On & off with the key will get the
> > pump to stop running! & will then start with fuel rail pressureized.
> >
> > Maybe??
> > $90 from Autozone + $90 core.
> >
> >
> >
> > "Jim Warman" > wrote in message
> > news:<joomd.163719$df2.31385@edtnps89>...
> >> First off.. stop swapping relays. Ford has a habit of "piggybacking"
> >> relays - i.e., one relay will control a device PLUS the control circuit
> >> of
> >> another relay. Swapping relays can have one trsavelling in circles.
> >>
> >> Second, the PCM does not look at fuel pressure to turn the fuel pump on
> >> your
> >> car on or off - when the key is first turned on, the PCM commands the
> >> fuel
> >> pump on briefly to ensure that the fuel rail is charged but it has no way
> >> of
> >> checking to see if, indeed, there is no pressure there. (This strategy
> >> didn't appear until the last few years).
> >>
> >> Are there no Continuous Memory codes displayed in the KOEO test? Also, it
> >> is
> >> essential that you complete the KOER test.... the PCM uses the dynamic
> >> response to test many sensors. I don't know which tool you are using nor
> >> what cues it gives for when to perform the switch test and dynamic
> >> response
> >> test but the switch test comes first....
> >>
> >> HTH
> >>
> >>
> >> "Gil" > wrote in message
> >> m...
> >> > have been through the entire fuel system....... except injectors.
> >> >
> >> > New fuel pressure reulator - easy
> >> > New fuel filter - easy
> >> > New fuel pump - bitch & 1/2 but warrentied no cost just 1 afternoon
> >> > work.
> >> > New/swap solinoids in fuse box - no brainer -
> >> > New inertia switch - easy
> >> >
> >> > Ok?
> >> >
> >> > It wont start some times when cold. Cranks over like a top
> >> > fuel pump runs & runs & runs till I turn off key.
> >> > it never stops, like its supposed to afer 2 seconds causing the no
> >> > start condition.
> >> >
> >> > When it does finally stop, maybe 30secs or upto a couple minutes at
> >> > times,
> >> > engine fires right up! runs great! but - see below:
> >> > When warm no problem at all- FP runs for 2 sec & stops, engine starts.
> >> > even after a few hours of sitting - seems like an over night time
> >> > frame will bring it on.
> >> >
> >> >
> >> > after running, engines idles smooth has good throtle response,
> >> > no check engine light.
> >> > but, after a few minutes of running, maybe 5 or so
> >> > check engine light on, idle is smooth, throtle responose now is poor
> >> > from 800rpm -2000rpm after that rpm its fine.
> >> > I can duplicate the above senerio just by turning off & restarting the
> >> > engine- warm or cold. Cold takes a bit longer for CEL to come on &
> >> > poor throtle reponse.
> >> >
> >> > Hmmmmmmmmmm.
> >> >
> >> > 2 seperate problems? I think??
> >> >
> >> > problem 1) fuel pump runs & runs - won't pressurize & turn itself off:
> >> > leaking fuel injector- only some times????
> >> >
> >> > Problem 2 check engine light - poor throtle response)
> >> > I cant get the codes from the check engine light KOER test because &
> >> > cant get the sequence of stomping the brake peddel & Wide open throtle
> >> > correct.
> >> > I get the code "no dynamic BOO WOT response" - blah blah - operator
> >> > error.
> >> > It could be the ECM not telling the injectors to fire properly?
> >> > especially in the no start condition? leaving injectors open? - no
> >> > fuel back pressure to turn off FP?
> >> >
> >> > Well whado I do? dive into the injectors? replace ECM?(I'm thinking
> >> > yes+ cheaper than new injectors)
> >> > Obviously there is no pressure in the fuel rail to turn off the new &
> >> > old fuel pumps, I can hear & feel the bubbleing in the fuel regulator
> >> > return line.
> >> > Its getting cold here in the midwest & this baby has to start
> >> > reliably, for the wife & kids.
> >> > I'm wishfull thinking & running Sea Foam fuel injector cleaner will
> >> > help.
> >> > Fingers crossed - not much hope in pour in tank cleaners.
> >> >
> >> >
> >> > Hope this all makes sense,
> >> > Thanks in advance!!
> >> >
> >> > Gil
> >> > (now 94 Explorer fuel system specialist trainee) NOT!!!!!!!!