[W126 Coupe] Re: Fuel problems

[Jazzman390 at aol.com]

If memory serves, the fuel flow is constant in this type of system, so the injectors are flowing continuously when the engine is running. I suppose a bad injector would flow more fuel than it's supposed to and wash the cylinder, but I'd think it also be putting out some black smoke as well. Or the 02 sensor would sense the rich mixture and change the EHA accordingly to (incorrectly) compensate. Hmmm.

What I was getting at is there is no pressure on the injectors when the engine is not running. No pressure--no fuel to run into the cylinder when the engine is off, even thought the fuel accumulator is doing it's job. 

Perhaps I'm missing your point.

Bob

In a message dated 1/21/2005 7:40:49 PM Eastern Standard Time, Jonathan Hodgman <jhodgman at gmail.com> writes:

>Well, here's the thing, the injectors are designed to hold about
>50-60lbs of pressure, but as the injectors become worn w/ age they
>stop holding that pressure and leak down into the cylinder walls.
>
>Jonathan
>
>
>
>On Fri, 21 Jan 2005 19:33:19 -0500, Jazzman390 at aol.com
><Jazzman390 at aol.com> wrote:
>> I've found that the fuel injectors have no pressure on them when the car is not running. Discovered this while troubleshooting a rough idle problem on the wife's 560SL. With and injector connected, turned on the key to run the fuel pumps (which they did for a second or two), but no fuel comes out. Tried it without the injector connected (just an oopen fuel line to the injector and there is still no fuel pressure (key on, but not cranking).
>> 
>> Thinking there was something drastically wrong, I repeated the test on my 560SEC, and it responded exactly the same way.
>> 
>> So, either both our cars have defective fuel systems but run just fine, or that's the way it was designed. If you've got fuel leaking into the oil, it's not the injectors.
>> 
>> Bob Cavazos
>> 
>> 
>> In a message dated 1/17/2005 12:09:34 PM Eastern Standard Time, Jonathan Hodgman <jhodgman at gmail.com> writes:
>> 
>> >Oh, I thought you were still running the old injectors for some
>> >reason.  That little computer is your EHA, which isn't really much of
>> >a computer, but that's neither here not there..  Anyway, try
>> >tightening the screws (or hex on later ones) that hold that bugger on.
>> > If it still leaks you need new o-rings.  I'm not entirely sure how
>> >the starting circuit works, but I do know that it is a closed loop
>> >affair in that it has it's own map separate from everything else.
>> >Do you have any means of warming up your garage?  Kerosene heater,
>> >space heater, something..?   Check your plugs and see if they're wet
>> >after cranking..let me know.
>> >
>> >Jonathan
>> >
>> >
>> >
>> >On Mon, 17 Jan 2005 10:44:22 CST, Pavel <zhur0002 at umn.edu> wrote:
>> >> Jonathon
>> >> I leaned it out a full turn (I know that is a lot).  The injectors
>> >> currently in the car are about 1.5 years old with about 2k miles on them,
>> >> so I think that they should be good?  Could they be bad?  I think that the
>> >> oil got dilluted because the car was running very rich, not because of
>> >> faulty injectors leaking into the motor.  I also noticed that a little
>> >> black computer on the side of the fuel distributor was leaking a little
>> >> fuel when the system was under pressure could that cause my problems?  Also
>> >> it is very cold outside about -8 degrees F, and 22 Deg F in the garage so
>> >> with that temp I would think the CO needs to be perfect to start the car.
>> >> Pavel
>> >>
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>
>
>-- 
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