jamieh

Are the injectors mechanically or electronically controlled?

Also What Pressure does the Fuel Pump work at, (roughly)?

EdzBenz

I wish I could answer these questions for you. Hopefully someone will be able to chime in. If not, also check out the www.mercedesshop.com website. There are a bunch of dieselheads on there that may know the answer.

I'm curious to learn the answer as well. I will take a guess and say that the injectors are electronically controlled.

uberwgn

There are no electrical connections to the injectors. I'm sure the FI pump would be condsidered electronically controlled.

The newest diesels inject fuel around 2000Bar. VW diesels built around the time of the W210 diesels were around 20,000 psi. The Benz is likely somewhat lower than 20,000 psi since it's IDI. I'd guess around 12,000 psi for the turbo cars...perhaps higher.

jamieh

Thanks guys,

If anyone else can clarify pls post.

240D 3.0T

The injection pump is electronically controlled. The injector nozzle pop pressure is 135bar (1,958psi). Feed pressure to the injection pump is about 14psi.

jamieh

Thanks,

Can you confirm that the injectors are mechanically controlled?

240D 3.0T

Yes, they are just nozzles. The injection pump and it's computer control the quantity injected.

jamieh

Would i be right in thinking then, each injector has its on link to the injection pump?

ie. 6 independent lines.

Diesel Benz

Sure, right.

jamieh

Thanks all for the replys,

As always its been a pleasure.

Have a good weekend and safe driving.

240D 3.0T

What are you trying to do?

harkgar

I am amazed at the difference in nozzle pressure between the old and new diesel engines - 10 times. Does it mean the old engines will last much longer than the new ones? With 20,000 psi you can cut rock sheets open with water.

240D 3.0T

The lifespan is not significantly different. The 20,000psi injection system was designed from the start for those pressures. It only becomes a problem when poorly designed aftermarket tuners crank up the rail pressure to get more power from the engine.

harkgar

It is good to know the electric high pressure injectors do not affect the longevity of the engine. I do not like certain features of my 2006 CDi and the two most obvious ones are:

1) The lack of dipsticks. I do not know why MB did that. The oil one returned in 2007.

2) The shrouding of the engine bay, top and bottom with black plastic. All leaks are hidden from view until the warranty is over. Maybe that is one of the reasons MB is using the suction method in oil changes too. There is no need to remove the bottom shield (savings in labor).

I had the oil changed today and found the transmission leaking from the "sealed for life" device. Same area as my sold E55 - where the transmission sensor goes into the transmission. Going to MB next week for warranty work!

jamieh

240D 3.0T - IN responce to you question "What are you trying to do?"

I'm just wanting to understand my engine better.

Thanks again.