My input was only related to the system holding the fuel pressure at
the fuel rail. If an injector is open that pressure won't hold simply
because of leak down at the injector. Reapplying that pressure at the
rail with a leaky or open injector will only spill fluid into that
one, or more, cylinders. While the engine may very well start after a
few key cycles the excess in the cylinder may wash the walls to the
detriment of the whole system. It may put too much in so that the oil
might get diluted in the pan.
On Sat, Aug 29, 2009 at 11:47 PM, Bernd D. Ratsch<bernd@dodgetrucks.org> wrote:
>
> If the PCM does not see crank rotation, the fuel pump will only run for a few seconds...regardless if an injector is stuck open or not. It doesn't look at pressure...but rather crank rotation.
>
> - Bernd
>
> -----Original Message-----
> From: John Dunlap [mailto:jsdunlap@roadkill.org]
> Sent: Saturday, August 29, 2009 4:03 PM
> To: dakota-truck@dakota-truck.net
> Subject: Re: DML: Fuel pump pressure.
>
>
> That only works if you don't have an injector stuck in the open
> position. Otherwise the pressure just goes to the path of least
> resistance, the one, or more, open injectors, thereby putting extra
> fuel into and one or more said cylinders. You want to talk about
> washing down cyl walls prior to ignition or just simply spinning the
> motor prior to ignition. Best bet is to get someone to do an injector
> pressure test, ie. dealer or darn good mechanic. You didn't mention if
> you are on reg gas or diesel.
>
> On Fri, Aug 28, 2009 at 11:04 AM, Azie L. Magnusson<maggie11@mchsi.com> wrote:
>>
>> Brian C. writes:: >> And how do you know it's a slow start due to that??
>> When you turn the key on, you can hear the pump kick on. No need to cycle
>> the key on and off. If the pump turns on it build pressure. Cycling the
>> key won't make it build up
>> any more pressure than the pump can make the first time <<
>>
>> I respectfully disagree Brian... When the ignition is turned on, the fuel
>> pump only runs for a couple of seconds(if for that long), and then quits
>> until the PCM gets a signal from the crank sensor that the engine is
>> rotating.. By turning the ignition off and back on you start the cycle over
>> and the pump again is on for the programed time and then turns off until the
>> engine is rotating. So, you get pressure build up by rotating the ignition
>> on & off a few times..... Forgive your enemies. It messes up their heads.
>> Azie
>>
>>
>
>
>
> --
> QUOTING... James Bovard
>
> "Democracy must be something more than two wolves and a sheep voting
> on what to have for dinner."
>
>
>
>
>
-- QUOTING... James Bovard"Democracy must be something more than two wolves and a sheep voting on what to have for dinner."
This archive was generated by hypermail 2b29 : Tue Sep 01 2009 - 00:06:01 EDT