104 engine (300 SEL 3.2) starting problem when sunshine

I had a very similar problem with my '97 E320. Perfect cold start but a
bit of delay on hot starts - hot start within about 2 hours of shut
down. I found stepping on the gas even a small amount allowed the motor
to start more quickly.

The cause was a leaking (#6) injector. I found it by removing the spark
plugs after the engine was cold. #6 was wet with fuel, the others were
dry, as they should be. The motor was perfect after the one injector was
replaced. Incidently, the problem started at only 18K miles when the car
was three years old but was diagnosed and repaired at about 38K miles
after ten years!
--

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 >> Stay informed about: 104 engine (300 SEL 3.2) starting problem when sunshine 

On 17 mayo, 15:54, "Tiger" <tiger0....TakeThisOut@hotmail.com> wrote:
> I am assuming it is the W140 body... so 1992+ model year. You are right
> about the injectors are leaking. Take the spark plug out and see which one
> is most fouled up... that would the be cylinder where that injector is the
> problem.... too much fuel.

after inyectors check wiring harness, i got that problem,
i asume was inyector, but finally where thas wires, all burned, ALL
 >> Stay informed about: 104 engine (300 SEL 3.2) starting problem when sunshine 

On May 17, 9:54 pm, "Tiger" <tiger0... DeleteThis @hotmail.com> wrote:
> I am assuming it is the W140 body... so 1992+ model year. You are right
> about the injectors are leaking. Take the spark plug out and see which one
> is most fouled up... that would the be cylinder where that injector is the
> problem.... too much fuel.

Thanks all.

Yes it is W140 body (but year 1991.. they started one year earlier in
Europe).

I waited until the morning. All plugs seemed dry and all with the same
(little) amount of coating. I tried to see on piston tops too, and
they were also dry. I tried to wait an hour while frequently spinning
the fuel pumps (but without starting). Still all dry.

That would indicate, that injectors are OK. Or are there some other
means to check it deeper?

Dr. Chino suggest wiring harness. Yes, they were bad some 2 years ago,
and I replaced the bad sections of the wires (soldered and insulated
with heat shrink tubes) at that time. Still there may be something,
and I may have to look in that direction again.

When i starts (when problem is present), it chokes somewhat in the
first 5-10 seconds or so, as if it has to get rid of the gas vapour,
and then it runs fine. Also it starts well when stopped for only few
hours. The problem occurs only when it has been stopped for several
hours while sun shines on the hood.

So I lean more towards a fuel system problem.

To my knowledge, once the fuel pumps have build up pressure, there is
only 3 ways, the pressure can escape: Output valves of the pumps (have
been replaced), pressure regulator (has been replaced) and injectors.
Plus, of course, leakage in the piping (no visible signs and no
smell). Am I missing something here?
 >> Stay informed about: 104 engine (300 SEL 3.2) starting problem when sunshine