W123 280e poor starting from cold Help please

[vito-dork]

cold starting is a real pain
its like trying to start a without a choke
but its Bosch injection
is there some sort of cold start mechanism ?
one it goes and gets up to temp its ok-ish
any ideas please

 

[vito-dork]

ok guys im still on with this cold starting issue.
i was told to check if there is power to the cold start injector (near to the distributor)
and yes when you crank the engine there is power but only a short burst ,, is that normal ?
thanks
W123 280

 

[alabbasi]

That's usually the cold start injector or a stuck aux air valve. Short squirt at the start is correct, the valve itself may not be functioning. You need to remove it and direct it to a cup to see it squirting.

 

[vito-dork]

not sure what or where the aux air valve is located or what it looks like..
i removed the cold start injector and it squirts lovely even masses of fuel out..
there is also another part to this i believe its a valve just at the n/s rear of the engine behind the oil filter housing
it has a plug,2 fuel pipes and a vacuum pipe , could this be cold start related too ?
thankyou so much so far guys

 

[alabbasi]

The auxiliary air valve is what controls the high idle on a fuel injected car. It's similar to a choke on a carb. It's going to be connected to a vacuum line somewhere on the intake side and looks like this.

 

[vito-dork]

hi alabbasi
i cant see a valve like that but there is something similar under the manifold on the engine,
it looks difficult to remove and maybe an inlet manifold off job (big job)
not sure i want to tackle it :-(

 

[vito-dork]

hi alabbasi
i cant see a valve like that but there is something similar under the manifold on the engine,

ive just found out the twin cam engine does NOT have a Aux air valve, so thats out

it looks difficult to remove and maybe an inlet manifold off job (big job)
not sure i want to tackle it :-(

 

[alabbasi]

ive just found out the twin cam engine does NOT have a Aux air valve, so thats out

Watch this if you're having trouble finding the AAV:

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Try adjust your high idle screw first. It might be turned all the way in.

 

[vito-dork]

Yes Alabbasi i already watched that and a couple more on youtube witch led me to believe mine did not have one
its quite visible on the video but mine is not, there is other stuff in the way and its hidden behind them
i do have a ramp in my garage and had a look this morning with a camera scope thingy and i think i can just see it but its not possible to get to without the inlet manifold off, why its so different ive no idea

 

[vito-dork]

update, please watch the video and pause it at 30 seconds in.
note the space to get to the aav (plenty)
mine has no room at all and the aav is not visible and it has other stuff bolted to the block and power steering pump of which ive no idea what they are for
plus several other pipes are in the way too inc from a front cooler to the auto box which i dare not disturb.

 

[alabbasi]

I can't imagine a CIS injected car (any CIS injected car) not having an aux air valve of some sort. Do you have an idle screw? In some cases, it's part of the same assembly.

 

[vito-dork]

yes i think ive found it hidden behind other stuff, not really accessable to me.
it has an idle screw too but it idles ok when warm.
when cold it just does not rev at all until warm then its fine.