egr bypass 606 turbodiesel - PeachParts Mercedes-Benz Forum

mdisav · #1 03-31-2006, 09:51 PM

After reading a good number of the posts on bypassing the egr on the N/A 606 and also reading how that modification will not work on the turbo 606 (which I agree), I am wondering if together we can come up with something that will work.

Am I accurate in assuming that because a turbo motor will not suck air in on the pressure side, it needs the pressure of the exhaust to have the exhaust enter the intake through the egr valve. So it seems to me that putting an airfilter in place of the exhaust tube even with a check valve ( so that boost is not lost) will not work and will set a code.

Someone mentioned (the guy with the upsolute chips) that he ran a wire from the egr solenoid to the mass air flow on his tdi successfully so a pressure or flow change was registered. But he did not know which one to do on the turbo 606. Maybe this is a viable place to start?

What about directing some of the crankcase ventilation in place of the egr tube somehow? Even if a check valve is to be used? Is the pressure close to or similiar to exhaust pressure? I am thinking it is less but maybe it is enough. I know the crankcase ventilation is on the suction side and it maybe impossible but I am just thinking out loud and throwing out ideas.

Anybody with some ideas? Anyone else been thinking hard about this?

Hatterasguy · #2 03-31-2006, 10:44 PM

My friend did this mod to his turbo charged 606. He did the "fresh air mod" that works on NA 606's. Pretty much put a little air filter on the EGR intake pipe. We got 1/4 of a mile down the street and the CE light came on and cut boost.

However I do not think boost was bleading off through the filter. When we first tested it in the garage their was suction. Makes sense exhuast gas needs to get pulled through that tube.

I suspect their is a temp sensor somewhere. Further study of the 606 FSM is needed. Their is probably a way to trick this sensor.

mdisav · #3 03-31-2006, 10:47 PM

What about the crankcase ventilation idea? It is warm...

mdisav · #4 03-31-2006, 10:49 PM

Maybe it is not a temp sensor but the manifold pressure sensor that is sensing things in the loop. The air filter idea has no pressure increase while the exhaust does and maybe the crankcase might provide.

Hatterasguy · #5 03-31-2006, 10:50 PM

Well that could cause a run away. I would be really carefull about feeding a diesel engine a potential supply of oil like that.

I am just speculating about the temp sensor, I couldn't exactly figure out what is controlling the air intake and the egr. Somehow the MAF is worked into this as well, in that black box known as the ECU. My friend doesn't have an FSM, I need to talk him into one.

I think it can be done, you just have to know how this engine works inside and out to figure it out.

mdisav · #6 03-31-2006, 10:56 PM

I figured that most of the gases would be going the normal route on the suction side and at wide open throttle the egr valve would be closed.

But then again that just may be why the crankcase ventilation is on the suction side. I definately do not want a runaway just trying to fool the egr!

Rafi · #7 04-12-2006, 01:38 PM

I would like to know all the facts please. If you would review the figure and add any information you have then we can see if we can experiment with it. Does anyone know how the pressure conver (53) works ? What does pressure sensor see at what condition etc.