[W126 Coupe] Cold Start Problem

[Jonathan Hodgman]

I've found the accumulators can contribute quite a bit to hard starting as well.

Jonathan



On Sat, 01 Jan 2005 22:34:56 +0000, Sharan Bains
<sharanbains@hotmail.com> wrote:
> Henry,
> 
> You'll see the cold start injector (CSI) right in front of the air filter,
> near the idle air valve.
> 
> It has one metal fuel line coming onto it and has a green/blue plug
> protruding from the side with a black loom coming into it.
> 
> The loom connecting to the green plug can be removed by slipping off the
> metal retaining clip which slots round the loom connector.
> 
> Using a 5mm allen key, remove the two 5mm allen bolts holding down the
> injector onto the inlet manifold. Leave the fuel line connected to the
> injector.
> 
> Lift out the injector and having removed the loom connecting to it, attach a
> ground and +12V to the two pins on the injector. It should spray out fuel.
> 
> (Of course, take safety precautions as fuel may be sprayed - ensure engine
> is switched off)
> 
> If it does not, then you have a faulty cold start injector.
> 
> Second test - with car stone cold, leave fuel line and loom connected to
> cold start injector, but lift injector out of manifold slightly and place it
> into a small plastic cup. Then turn engine for a few seconds. You should
> find that there is a small amount of fuel in cup.
> 
> If not, then cold start sensor is likely faulty. This is the 4 pole switch
> on the manifold. It can be checked for resistance values....Chet is the man
> for the values you should be reading here.
> 
> Check integrity of loom coming into CSI.
> 
> Other reasons for your hard cold starting - bad injectors (clogged or
> leaky), wrong spark plug spec, faulty fuel pressure regulator (the one on
> the side of the fuel dist). Your idle air valve maybe sticky too. Check the
> air metering plate too for absolute clearance from intake walls.
> 
> talbir
> 
> >From: "Henry Viveiros" <henryviv@grantspass.net>
> >Reply-To: mbcoupes@mbcoupes.com
> >To: "Mbcoupes@Mbcoupes. Com" <mbcoupes@mbcoupes.com>
> >Subject: [W126 Coupe] Cold Start Problem
> >Date: Sat, 1 Jan 2005 12:05:17 -0800
> >
> >My 1991 560 SEC starts fine when the weather is mild (above 50 degrees).
> >When the outside temperature is less than that it starts and instantly
> >stops. It will start the second time I try it. It was this way last season,
> >was OK during the summer, and now that the weather has become cool again,
> >it
> >is doing the same thing again.
> >
> >I think I have read something about the Cold Start Valve. Where is it? What
> >does it look like? What can I do to check it?
> ><< winmail.dat >>
> 
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> Postings remain property of MB Coupes, L.L.C.
> 


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