Cis system in 190e

[benjyman]

Hi reading and learning lots about my myterious injection system on my merc 190e 2litre, its a bosch cis system.

The problem seems to be with the metering head (fuel distributor) or the injectors, there seems to be an abundance of fuel at 1 and 3 injectors and 2 and 4 are lean, now for the question is this a fault of the metering head (read expensive) or is that the injectors at 2 and 4 are blocked thus sending the over pressurised fuel to the other injectors in the system ??

Oh.. and the injection system has developed whinning squeak like its under a lot of pressure if this helps ?

 

[benjyman]

Hmm... Still not making progress with this engine, the injecors seem to be over pressurised, making me think the return valve/ cold start valve may be at fault ?

 

[ukhozi]

Mine did the squeaking thing too, broken ceramic plate in the distributor valves
Upper chamber pressure is the same to all 4 injectors, so if you have 2 rich and two lean it has the be the injectors themselves as the pressure is common to all 4 OR the distributor has two knackered valves and two good ones, only way is to check pressure on all 4 lines.