2005 E320 CDI seems underpowered - PeachParts Mercedes-Benz Forum

65aircooled · #1 04-28-2014, 09:12 PM

Quote:

Originally Posted by grease lightnig

You said you did the sensor on the back of the fuel rail. The one on the back of the fuel rail can not be changed it is set at the factory and the book says to change the whole rail if that is a problem. Mercedes does not change them at the dealerships just the rail. If you removed that sensor. I am willing to bet you got it in there good enough for it to run without an error code but not as good as the factory settings. It is adjustable maybe before you buy a new one for $325 you should micro adjust it. I think you should mark the rail in both directions and mount a pointer on the sensor. Adjust it left one notch and then test it. Adjust it right one notch. Until it runs really good. If it starts to throw code you know you did it wrong.

Good Luck with that.

Quote:

Originally Posted by E300D

I have purchased a new one and we actually swapped it out and it did not make a difference at initial diagnosis. It was a sensor at front of the hp pump.

From what I have heard, the press regulator is not adjustable.

Thanks

Why do I ge the feeling that you guys are talking about two complete different things? HP pump and fuel rail...

polarisrmk · #2 05-01-2014, 01:03 AM

The bio diesel has ruined your injectors I have seen this many times ... There is a tester for the leak quantity of the injectors if u want to confirm but pretty much garuntee they are ruined as well as the pressure regulator

Skid Row Joe · #3 05-01-2014, 02:31 AM

After being away adventure travelling for almost a month, I returned home to Texas and once again have the pleasure of driving my 06 E320 CDI every day or so a few miles - it struck me that it is almost; overpowered, if anything. You have to watch that these massive-powered creatures don't get away from you when pushing the throttle on 'em. I am thinking that the foreign versions of the 05/06 E320 I6 CDI, the E270s, are probably a little more tame to handle and better mated for power, than these monster-powered 3.2 liter turbo sedans that we have here in the States.

grease lightnig · #4 05-01-2014, 05:18 PM

Did you change the back of the Common Rail "We did the sensor at back of fuel rail." Because that would be bad. I was wrong I looked it up a new rail is $750. And Yes I have a spare in my garage that has an adjuster nut on it. It might not be adjustable but it can be adjusted.

E300D · #5 05-01-2014, 11:20 PM

Drove the car today. Running smooth and no smoke. Fuel pressure rail peaks at about 23000 psi..turbo peaking at 32 psi...

The dealer has flow tested the injectors before I bought the car..not sure if I can trust them or not..they also performed engine compression test. All seemed to be well

So if I am peaking at 23000 psi ..how could the pressure regulator at back of rail mis adjusted?

How can injectors be fried if car runs smooth and no smoke.

It seems like a software or sensor issue..but ..

jcyuhn · #6 05-02-2014, 10:34 AM

If the injector spray pattern/atomization is messed up, I can see the results being low power and poor fuel economy due to poor combustion - it kinda makes sense. But then I would also expect there to be an observable difference in the way the engine runs - either idle noise, or perhaps additional black smoke under acceleration.

Unfortunately the piezo injectors are very expensive (~$500 each), so swapping them on speculation isn't feasible. I wonder if there are services which can test/evaluate/recondition them?

65aircooled · #7 05-02-2014, 06:33 PM

Quote:

Originally Posted by jcyuhn

If the injector spray pattern/atomization is messed up, I can see the results being low power and poor fuel economy due to poor combustion - it kinda makes sense. But then I would also expect there to be an observable difference in the way the engine runs - either idle noise, or perhaps additional black smoke under acceleration.

Unfortunately the piezo injectors are very expensive (~$500 each), so swapping them on speculation isn't feasible. I wonder if there are services which can test/evaluate/recondition them?

No Piezo injectors in the CDI, still won't be cheap tho