
Signature
Max
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
> > Sorry Max, but you said that it will not monitor MOST fuel problems and it
> > in fact will.
>
> And in fact it won't. Here is a short list of what the PCM has no clue
> about: Fuel filter, fuel pump, fuel lines
Lean run condition
, fuel injector spray pattern,
> clogged fuel injectors, failing fuel injectors (it knows if it fired the
> injector, but it doesn't know if that event went well)
Misfire codes
fuel pressure, fuel leaks,
These are really just repeates from above
grade of fuel,
Is not a delivery problem
if water is in the fuel (the diesels know this, but
> not the gassers, AFAIK) or if the fuel is even capable of igniting, as in,
> varnished or aged.
Again, non of this is a delivery problem
> > Absolute fuel pressure is the only thing that it will not
> > monitor but just about every other fuel delivery problem will cause
[quoted text clipped - 3 lines]
> Um, yeah, except the problem YOU mentioned first was a failed fuel pump,
> which is not monitored.
It depends on what failed. A complete failure will not be detected but a
partial failure (very low pressure) would show up as lean run and misfire
codes.
> This is directly related to fuel PRESSURE, which is
> not monitored. Further, if it was enough to get the truck going, but not
> enough to properly spray from the injector, there would be an atomization
> problem, which is not monitored.
Did you forget about misfire codes. It would also probably result in rich
run codes that would be false but would indicate a fuel delivery problem.
> > You are of course correct that
> > he should get the codes before proceeding but to say that most fuel
[quoted text clipped - 3 lines]
> Its absolutely correct. The only thing the PCM knows about the fuel is
> injector timing and A/F mixture via sensors.
And fuel delivery problems severe enough to cause running difficulties are
doing it why Max, because it will cause the very mixture problems you just
said so I guess that they are monitored indirectly after all.
> > Now if you had said directly monitored, you
> > would have been much more accurate but since you like to jump on me for
> > crap
> > like this, what comes around goes around.
>
> Nah, I just jump on you for crap where you are wrong.
If that were only true but we both know better than that. Have a Merry
Christmas Max.

Signature
If at first you don't succeed, you're not cut out for skydiving
Max Dodge - 20 Dec 2005 03:28 GMT
>> And in fact it won't. Here is a short list of what the PCM has no clue
>> about: Fuel filter, fuel pump, fuel lines
>
> Lean run condition
A lean run condition doesn't necessarily point to the fuel system. On the
chance that it does, it does not pinpoint a cause. As such, a lean run
condition only points to a lean run condition, not a cause. From there, it
takes a trouble shooting procedure to determine cause.
> , fuel injector spray pattern,
>> clogged fuel injectors, failing fuel injectors (it knows if it fired the
>> injector, but it doesn't know if that event went well)
>
> Misfire codes
Misfire codes indicate that a cylinder did not fire correctly. It does not
indicate why the cylinder fired incorrectly.
> fuel pressure, fuel leaks,
>
> These are really just repeates from above
Unfortunately, they are not. They are problems unto themselves, not just
symptoms.
> grade of fuel,
>
> Is not a delivery problem
Sure it is. If for some reason the fuel vaporizes in the line, (rare, I
know) the PCM would never know it.
> if water is in the fuel (the diesels know this, but
>> not the gassers, AFAIK) or if the fuel is even capable of igniting, as
>> in,
>> varnished or aged.
>
> Again, non of this is a delivery problem
Unfortunately, you are wrong. Fuel varnish can clog injectors, stall pumps,
and doesn't burn very well, if at all. If it doesn't burn, its not fuel,
thus fuel isn't being delivered. Same is true of water in the fuel.
>> > Absolute fuel pressure is the only thing that it will not
>> > monitor but just about every other fuel delivery problem will cause
[quoted text clipped - 5 lines]
>
> It depends on what failed.
No, it depends on what you said failed, which was the fuel pump. And what
you said failed, is NOT monitored by the PCM.
> A complete failure will not be detected but a
> partial failure (very low pressure) would show up as lean run and misfire
> codes.
While true, both codes could indicate other problems. That is why its
essential to get all info, since the fuel system will not show any dedicated
codes.
>> This is directly related to fuel PRESSURE, which is
>> not monitored. Further, if it was enough to get the truck going, but not
[quoted text clipped - 3 lines]
> Did you forget about misfire codes. It would also probably result in rich
> run codes that would be false but would indicate a fuel delivery problem.
See above. There are no dedicated fuel delivery codes.
>> Its absolutely correct. The only thing the PCM knows about the fuel is
>> injector timing and A/F mixture via sensors.
>
> And fuel delivery problems severe enough to cause running difficulties are
> doing it why Max, because it will cause the very mixture problems you just
> said so I guess that they are monitored indirectly after all.
OOPS, what did you say? INDIRECTLY? Right. INDIRECTLY, you could use the
codes to find a problem, and THEN use deductive reasoning (troubleshooting)
to INDIRECTLY find the problem in the fuel system. But there are no
dedicated codes, nor any sensors monitoring, the fuel delivery system.
> If that were only true but we both know better than that. Have a Merry
> Christmas Max.
Who is we? I'd love to see a list of people you think agree with you
consistantly.

Signature
Max
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
>> > Sorry Max, but you said that it will not monitor MOST fuel problems and
> it
[quoted text clipped - 67 lines]
> If that were only true but we both know better than that. Have a Merry
> Christmas Max.