w123 230ce

[stretch]

hi there anybody no how to adjust the auto choke as mine don't work when cold it ticks over 700 rpm when warm its at 900 rpm its been like it since i got her just had new cam chain and drive sprockets s one was worn right out the timimng is spot on pulls like a dream when warm or going but start up is not that good stalls lot if i don't get it some thanks

[mylittletony]

if I had a million pounds, I would bet a million pounds that it's something to do with vacuum hoses and/or the metering head.

the injection system is "very" sophisticated on these, but as a penalty also very complicated...

there's a huge amount of info on owners' forums here and here

good luck!

Dec 19, 2011 13:51:46 GMT stretch said:

hi there anybody no how to adjust the auto choke as mine don't work when cold it ticks over 700 rpm when warm its at 900 rpm its been like it since I got her just had new cam chain and drive sprockets s one was worn right out the timimng is spot on pulls like a dream when warm or going but start up is not that good stalls lot if I don't get it some thanks

[stretch]

thanks will have a look when it stops raining lol

[gpzephyr]

Hey cool, another w123 230ce on here.

Mine starts and runs great luckily. Try looking for the cold start injector and make sure the connections to it are sound, could be something as simple as that. I'll check my manual tomorrow and give you a few more pointers.

[Onne]

Where would one find the cold start injector? Mine struggles to start, but only when ice cold in the morning (it tends to be ok after work)

[TurboDieselWeasel]

The metering unit is probably one of the most wrongly replaced items on these ;D They hardly fail...

However, the warm-up regulator can play up sometimes. It's too fully mechanical, apart from being electrically heated:



That's the K-Jetronic's 'choke' in a W123.

Very basic operation principle: the system has a certain pilot pressure (fuel pressure) which is used for fuel metering. The warm-up regulator adds more pressure to the pilot pressure to richen the mixture untill the engine is warm (there's a simple bi-metallic valve in the regulator, electric heating is for setup/adjustment of the valve).

To determine if the warm-up regulator works, this pilot-fuel-pressure resp. de- and increase of the pressure, can and should be measured. But I don't have the data at hand right now. Maybe you could just swap it for a known working one?

The cold start valve works only immediately after starting the engine and should be inoperative 10-15 seconds after the engine fired. At a wild guess; this is not your culprit

Cheers,
Jan

PS: it's a fully mechanical fuel injection, the only rudimentary electronic part is the fuel pump relay which also works as a rev limiter Beautifull, isn't it?

[stretch]

cheers for that think i now what you mean will have a look whats the screw be side that red arrow for then?

[khimanimohiki]

sounds like the idle air valve or idle speed control relay, basically an electronic choke valve which opens and closes to maintain your idle speed.