Fuel injection timing of Common rail engines 1

[valgaroc]

I know how to adjust fuel injection timings of MC engines.
But, In CR(Common rail engine) I don't know how to adjust it.
The only thing that I know is it is controlled by solenoid valve.

and, It is possible to control fuel injection timing on engine side? Is there any cam shaft or fuel rack in high pressure pump?

 

[thruthefence]

manifold pressure?

 

[tbuelna]

vagman2 is correct. It would be unwise to alter the timing sensors on a digitally controlled CR diesel system unless you really understand what you are doing. Most production diesels are firing pressure limited, and if you screw-up by injecting too much fuel too early in the cycle you can easily damage the pistons, rods and crank. Unless you have some sort of cylinder pressure indicator feedback (which most engines currently don't have, and would be a very expensive type of instrument to add even for testing:

http://www.avl.com/wo/webobsession....XMmcGFnZT12aWV3JiZub2RlaWQ9NDAwMDEzMjQ5.html)

you have no way of preventing excessive firing pressure loads.

Most current diesel ECU systems are still open loop with regards to firing pressures. They avoid excessive firing pressures only through careful mapping and use of control laws with inputs coming from measurements of various temperatures, crank speeds, various pressures, and load demand. In the near future, production engines will close this firing pressure feedback loop with pressure sensors built into the glow plug:

http://www.beru.com/english/aktuelles/presse/20080131-PI274.php

Four stroke engine controls (gas or diesel) always require two separate angular position feedbacks (one on the crank and one on the 1/2 speed cam drive) so that the engine knows whether it's on the power stroke or intake stroke.

Good luck.
Terry

 

[vagman2]

The VAG's V6 TDI CR engine is the one they speak about in that site.