[Diesel Nut!]

I am working on the above car. Very hard starting, poor idle until car warms up. Have to keep feathering accelerator until engine warms up enough. Once warm, runs fine. I found the control for the cold start, the sensor threaded into the front top of the cyl head, was bad. I say it's bad because the two terminals on top show one terminal to ground to have resistance, and the other, whos connections traces back to the csi, to be wide open always. I replaced the unit and still no function. I seem to be missing my 12v to the csi unit itself. My question is, where does the csi system get it's 12 v from? Is the second terminal in the sensor for a thermal heating element? If so, does this element who has 0v as well get it's 12 volts from the same source? I'm assuming that there is either a timming unit or the 12v is constant with the key on? If anyone has a wiring diaram as well it would be a great help. thank you in advance.

Rick

Spent some time today going over some things. Here is what I found. I'm not sure exactly what temperature the cold start injector is to start functioning. I do know if I bypass the temp sensor in head, the engine floods when it tries to start. So, maybe it's not cold enough for it to function yet? 2nd, Engine stumbles and refuses to idle on own for the first few minutes. Upon checking things further, I found what I think is an Air Temp sensor located under air intake. I get an infinite reading hot or cold. When I jump the sensor wires together, idle drops noticeably once engine is warmed up. Does anyone know if this temp sensor is just a switch, on-off, or is it a variable sensor, IE a temp sensitive resistor that changes resistance with temp?

 

[mrisf01]

I had a similar problem on my 1993 190e. After trying just about everything i took off the air intake/fuel injector assembly. The underneath of this assembly is molded rubber which had 2 splits in it, a 'starburst' and a crack. I visited 3 car breakers yards and had a look at the ones they had there(took a while in the cold to get them off) and they had the exact same split pattern. I searched the internet for a replacement but could not find one so I got a piece of 5mm thick rubber, cut it to shape and super glued them over the splits...no more problems since then.
Worth a look mate.

 

[tjts1]

Some people simply trigger the cold start valve manually with a switch in the dash.

 

[Jippi]

have u checked the ovp??