What is wrong with my 606? - PeachParts Mercedes-Benz Forum

zitobenz · #1 09-07-2015, 09:13 AM

Car: 1999 E300 Turbo Diesel

I removed the cylinder head and had the stuck glow plugs removed. Put the head back on and everything seemed fine at first but after a two hour round trip it started idling rough. I checked under the hood and there was exhaust coming out of the cylinder head cover port for injector #2 . Upon further inspection we figured that the locking ring collar that holds the pre-chamber in place was not torqued properly. I purchased the Spline Socket from the dealer, removed the cylinder head cover and injectors and tightened all six collars to 130 Nm. It is still idling rough and I have very little power accelerating from a stop, but it is much better when it gets through second gear.
It is showing P0300 and P0380 error codes.
Here is a link to a video of the engine and exhaust. I don't know if you can tell much from it but at the end you can hear the missing sound from the exhaust.

https://youtu.be/-VfbZ5cCzEA

One other thing happened but I believe it was caused by a bad fuel return hose. I replaced the suspect hose and it hasn't happened again, but I will mention this in case it points to something else. After reinstalling all injectors and hoses, I took it for a test run even though it was idling rough. It all started good but after about 15 minutes i smelled diesel fuel. When I checked under the hood, all six of the injector ports in the cylinder head cover were filled with diesel fuel.

What the heck have I done?

barry12345 · #2 09-08-2015, 10:49 AM

Sounds like they may have pulled some of the pre chambers to deal with the stuck glow plugs? How many plugs where really stuck bad?

Was the head also resurfaced when off? I only responded because the responses to your post seemed slow. You did put new return hoses on?

I know little about your issue but I might want to talk to the people that removed the stuck glow plugs. Only reason that I can think of to remove all the pre chambers would be to machine the head surface. I might even be wrong there.

If there where too much head material removal their might be issues. Just some wild guesses by me to your post. You did use all new heat shields I assume and where sure the old ones where out.

Murkybenz · #3 09-08-2015, 12:20 PM

Code p0380 is glow plug related and p0300 is detection of a misfire according to google
So simple things first
Leak off pipes don't fit very well and leak fuel and let air into system causing rough running .
Glow plugs remain on and cause misfire ?.
Egr valve is playing up.
Vacuum pipe come adrift somewhere ?.

Fairly sure its something simple and the fact its awash with fuel / smells of fuel points to an easy fix .
The smkke from tail pipe is grey ish in colour so it would lead me to think its running lean -- couple this with fuel leak -- so air in fuel causing rough running and hence no power is my guess.

zitobenz · #4 09-08-2015, 12:22 PM

Car: 1999 E300 Turbo Diesel

I removed the cylinder head and had the stuck glow plugs removed. Put the head back on and everything seemed fine at first but after a two hour round trip it started idling rough. I checked under the hood and there was exhaust coming out of the cylinder head cover port for injector #2 . Upon further inspection we figured that the locking ring collar that holds the pre-chamber in place was not torqued properly. I purchased the Spline Socket from the dealer, removed the cylinder head cover and injectors and tightened all six collars to 130 Nm.

Now it still idles very rough and low and it has very weak acceleration from a stop but is better after shifting into third. It also blows a tremendous amount of white smoke out of the exhaust. The Glow Plug light stays on and the engine is throwing a P0300 and P0380 code. The car starts prerfectly fine on the first time.

It ran fine after initially reinstalling the head but now I have all of these problems. I removed all of the injectors and had them cleaned and tested. I checked the fuel lines and they are fine. Could this be some sort of timing problem? What could cause all of the white smoke from the exhaust?

I took a video of the engine running. I don't know if you can tell much from the first part, but you can see the white smoke coming from the exhaust and asctuall hear the engine "missing" at the end of the video.

https://youtu.be/-VfbZ5cCzEA

What the heck have I done?

MyOld240D · #5 09-08-2015, 10:01 PM

This sounds and looks like air in the fuel system.

zitobenz · #6 09-08-2015, 10:37 PM

Thank you for the ideas, I will try to address each one.
The head was not machined, only drilled for stuck glow plugs and rebuilt.
I have attached all new fuel return hoses and made sure that they are tight (no leaks).
I disconnected the glow plug relay to see if a glow plug was "stuck" on and causing a misfire but nothing changes.
I tried to check all vacuum hoses but don't see any trouble there.
I hope it is an easy fix, but the car was running fine before the long test drive.
Is there any damage that could have occurred from the exahust escaping through the #2 prechamber/injector port?
Could there be a timing issue or perhaps a fuel filter problem?
I have had all of the injectors tested and cleaned, no problems there.
Lastly, there is really a tremendous amount of white/grey smoke from the exhaust when accelerating from scratch.

zitobenz · #7 09-09-2015, 09:33 AM

MyOld240, Would air in the system cause the extremely rough idle? I don't see any bubbles in the fuel lines so where do you think it would be pulling air into the fuel system? I also do not have any fuel leaks.

Maxbumpo · #8 09-09-2015, 09:54 AM

Given that you've had the hard fuel lines off and the injectors out, there is a possibility that one or more injectors have been contaminated with dirt and now aren't injecting like they should.

You could try loosening the hard injector lines one at a time to see if you can determine which injector(s) are responsible. Engine running, loosen each line slightly so the fuel starts to leak out, and see if the miss changes. If it doesn't change, or changes less than when other lines are cracked open, then you may have found the responsible injector.

zitobenz · #9 09-09-2015, 10:37 AM

That is a great idea, I will perform that test this afternoon and report back.

Murkybenz · #10 09-09-2015, 02:15 PM

If no joy from the above test then check egr for correct function as it may be sticking

zitobenz · #11 09-09-2015, 02:45 PM

Thank you for the input. I am on my way to test the injectors now. I am unfamiliar with how to test the EGR valve. Can anyone enlighten me on what I need to do to see if it is functioning properly?

zitobenz · #12 09-10-2015, 05:57 PM

I used a new head gasket and new bolts, followed the instructions to the letter. The interesting thing is that it ran fine on the initial test drive and now it is smoking like crazy and experiencing rough idle and lack of power on the low end. Either this is a random fault somewhere that is totally unrelated to the rebuild or it was caused by driving the vehicle while there was exhaust coming from the #2 injector hole/prechamber.

zitobenz · #13 09-29-2015, 09:58 AM

I went to take it for a test drive and after two blocks it started making a very loud clacking/knocking noise. I took a video of it but it is much louder in person than the video shows. Does anybody know what this could be?? In another forum one of the members said that I have a timimg problem with the engine or IP or both. So here are my questions so I can continue to troubleshoot:

1. I did not remove the IP when I removed the head, could the IP timing be off anyway? If yes, is there a procedure in the Stickies for setting the IP timing in the 99 606 engine?

2. The only way I know to check the timing is to remove the camshaft cover and rotate the engine clockwise to TDC and check the marks on the camshaft gear. Is there an easier way to do it?

3. How do I check the EGR functionality?

zitobenz · #14 09-29-2015, 10:00 AM

Here is the video:

https://www.youtube.com/watch?v=Ckxhwgx6GzE

barry12345 · #15 09-29-2015, 10:38 AM

Problem is it ran well after you assembled it and went on a trip? Something has let go since and is getting worse.. Inspect the valve train components very carefully. The injection pump timing had to be okay as it cannot self shift.

Unless the chain has jumped somehow and that is only possible on the camshaft. The noise now is too pervasive to test drive on and seems to be getting much worse. I was even thinking maybe the cam gear key was not installed properly or had sheered. That is a very long shot though. Even a broken cam is another very long shot.

Sounds very mechanical to me as well. Broken valve spring? I am not the greatest person to offer advice on engines as I am not a working mechanic. Also diagnosis by video has it's limitations. At least by me.

Sounds like you have a miss plus noise though. Rather than something like nailing. Rotate the engine when inspecting the valve train by hand. That's if nothing obvious jumps out at you. I hate to use logic but the valve train was the last signifigant area that was worked on. Historically that is where the effort to find the issue should be concentrated on.

Or to put it another way. I suspect if I gave you another good complete head and you installed it the problem would probably be gone. Let us know what you find. Do not get up tight as it may be a small issue. When I do get up tight or something is not going easy I just walk away from it for awhile. You probably did nothing wrong. The white smoke is unburnt diesel fuel.