Gas in the oil, HELP :(

[dan.bubb at gmail.com (Dan Bubb)]

It is absolutely a good idea to compare the flow from all the
injectors and make sure they are even. Unfortunately if they aren't
the problem is more likely the metering unit rather than the
individual injectors.
The injectors are really just atomizers with a low pressure shut off
valve ~35 psi.
They don't determine how much fuel to flow, that is done by the metering unit.
Basically if the injectors don't drip when there is no flow to them
(not testable for Lexan currently) and they have a nice spray pattern,
then they are OK.
System pressure won't cause the injectors to flow if the rest of the
system is set up correctly. She may have high system pressure, but the
injectors flowing with no airflow doesn't indicate that. The system
pressure can be sky high, but if the metering plunger is in the
correct position for no flow where the plunger blocks off the metering
slits, then indeed there will be no flow.
Bottom line here is that the metering plunger is too high with no
airflow uncovering the metering slits to some extent.
What's causing that is either a sticking plunger, the airflow plate's
stop is adjusted too high, or the mixture adjusting screw is adjusted
way in.
my .02
Dan

On 3/20/07, Karl Krupke <kkrup62@hotmail.com> wrote:
> Hi Lexan,
>    Good to hear you've found the fuel source, now to find out why the
> injectors are open.
>    I think it's got to be one of two options; 1) all 4 injectors are leaky.
> Possible, but I'd think they wouldn't all leak at the same rate and
> pressure. You can use your beer bottle set up to check (I'm assuming all the
> bottles are the same type and volume); just put one injector in each of four
> bottles, jumper the fuel pump relay, fill the bottles about 1/2 or 2/3 full.
> All the bottles should have the same amount of fuel in them, or damn close.
> If this is the case, then I think you can say your injectors are OK. But if
> there is a marked difference in the fuel volume in the bottles, then you've
> got one or more bad injectors. They're not horribly expensive, so replace
> all four.
>    And option 2), if the injectors are all OK then something is causing the
> system pressure to be higher than it should be (above the cut off pressure
> of the injectors, about 33psi I think?), thus
> all injectors are open and spraying. Sticky plunger in the fuel distributor
> block maybe? I'm not going to speculate on how to troubleshoot that, just
> read your Bentley. I don't know the history of your car, but if it's been
> sitting for a long time (months) it's possible that the fuel has broken
> down. Very old fuel can become almost like molasses; thick and gooey and not
> at all friendly to precision components such as Bosch CIS. Sounds like you
> are getting fuel flow through the entire system, so perhaps using a fuel
> cleaning additive might help free the plunger if that's the problem (I've
> used BG products in the past and had good experiences, also good is a little
> bit of Marvel Mystery Oil in the fuel tank (1/2 quart MMO to 10 gallons
> fuel), though this will burn a little blue. You'll need to run a couple more
> tanks of untreated fuel before you do an emmisions test.
>
> Karl
>