I posted about a week back about a rough idling SD. Update and new questions:

it still idles rough. I did clean out the intake manifold line that runs to the vacumm valve. It was about 1/2 clogged. But no effect on the idle problem.

According to the W123 manual, it could be a faulty injector pump, clogged injector, worn timing chain or worn cam lobes.

Concerning the lack of power, I determined that the engine doesn't have any power when the hose running from the valve cover to the air cleaner is connected to the air filter housing.

I disconnected this hose and the car runs like a scalded dog. But it definately won't burn that oily air coming from the crankcase.

It smokes blue smoke bad. Someone said the valve guides/seals could be leaking oil, but I haven't checked that far.

Any thoughts?

Dumb question:

Are you sure the air filter or the air intake is not somehow restricted? How clean is the air filter?

I find it hard to believe that you have enough oil vapor to affect the engine power.

The air filter is brand new, installed today. I completely disassembled the filter housing and all the air intake plumbing associated with it and thouroughly degreased it prior to installing the filter.

Unless the assembly that the engine ventilation hose plugs into is somehow clogged, I'm at a loss. That cannister is permanantly sealed and doesn't look like it is supposed to be serviced.

I dunno...

What happens if you put a new hose from the valve cover to air cleaner on? I know someone on this forum had a semiblocked crankcase hose doing the same thing.

__________________
-disav

99 E300 TURBODIESEL Astral Silver 282K - AMG brakes, suspension, monoblocks, speedo & interior - Full Load Maxed on IP by custom Speed Tuning USA Chip - T3/T4 Garrett - EGR/MAF delete
98 E300 TURBODIESEL Alexandrite Green on black leather 289K
95 E300 DIESEL Green Queen 267K SOLD
84 300D 216k SOLD
87 300D 299K #22 head - intercooler - full load adj. - 8sec 0-60mph - SOLD
76 300D 214K SOLD

With the hose attached, are you building up pressure in the crankcase, partially activating the shut off valve and reducing fuel to the IP?
We know that if you completely seal off the crankcase by plugging that tube, the engine will shut down.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

with the vent hose properly attatched to the air cleaner assembly, the engine will not rev above 2800 rpm. It doesn't have enough power to shift the trans out of first or second. I can have the pedal to the floor, the engine will rev to 2800 or so and then will drop to idle and then will rev again, but it will not run above that rpm or even stay there once engine speed reaches that rpm.

I'm not a mechanic by any stretch of the imagination, so I don't know anything about crankcase pressures or a "shut off valve" reducing fuel to the IP. And, yes, the engine will stall if that hose fitting on top of the valve cover is sealed; I did that out of curiosity last week, not realizing that I had this problem we are now discussing and the engine did stall.

Now as I sit here and type, I realize I have not verified that the hose is free and clear of blockage. That probably should be my next box to check. I was assuming the engine couldn't burn the oily air coming out of the engine. I was planning on routing that air down to the bottom of the engine bay and gone, but I guess I should check the hose for blockage first.

Did I mention in the last few sentances I'm no a mechanic but I play one on TV?

Thanks for all the help.

I agree, you should check the hose next. I still don't believe you could have enough oil vapor going to the intake to "choke" the engine.

I'm sticking with my hypothesis. You're building up crankcase pressure and doing something to the shut off valve which reduces fuel. Put a hose on to the assembly at the air filter and see if you can blow through it. If it runs ok when the hose is unattached, the blockage must be between the location where you are unattaching the hose and the intake manifold.
Another test would be to reconnect the hose and run the engine with the oil fill cap removed. That will stop pressure from building up in the crankcase also. That should tell you whether the problem is from crankcase pressure or from something else related to attaching the hose.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Is there any chance that the hood or the hood pad is putting pressure on the breather hose only when the hood is closed?

__________________
Palangi

2004 C240 Wagon 203.261 Baby Benz
2008 ML320 CDI Highway Cruiser
2006 Toyota Prius, Saving the Planet @ 48 mpg
2000 F-150, Destroying the Planet @ 20 mpg



TRUMP .......... WHITEHOUSE
HILLARY .........JAILHOUSE
BERNIE .......... NUTHOUSE
0BAMA .......... OUTHOUSE

I suppose it's possible that the hood insulation is pressing down on something, but I tend to think that's not the issue. The insulation is so old and crumbly, it dissinigrates as soon as it's touched.

I cheched the hose assembly last night and they are clear. My other thought is of the cannister inside the air cleaner housing; what is it and could it be blocked?