'98 606 fuel/air delivery problems??? - PeachParts Mercedes-Benz Forum

Carleton Hughes · #1 08-08-2006, 09:36 AM

I refuse to lose my temper over this,I love the car{'98 E300 Turbo Diesel}despite it's rare problems.
But there's nothing that can't be fixed with a little patience and thought,here goes......

For the past year the following symptoms would occasionally occur.

The car would start and idle well when cold,but after 1.5-2 miles would suddenly lose power in a puff of white smoke so i would pull over,feather the accelerator while in park waiting for the temp to rise which seemed to get it over the hump.after another 2-3 minutes and all was well,never happened when the engine was warm or hot,only on cold starts in the morning. This didn't happen all the time,but regularly enough,no check engine warnings apeared at the time.

Yesterday it reached the point where it will do this continually after the non-problematic cold start,this time letting the car idle it out and warm up had no effect,and the check engine/engine electronics lights came on after a hard,smoky,limp home pull up my hill,wouldn't do even 10mph.

I have searched thru the archives and have read the following probable causes,dirty EGR,Pre-Filter&O ring,K-40 relay,intake resonance valves{where are they?} or throttle switch.

I'm going to pull the manifold today and see what's going on in there.

Anybody else successfully resolve the same issue? the symptoms seem too regular to be a fluke,Please share your experiences with me before I replace everything,sorry for the length of the post.

sokoloff · #2 08-08-2006, 09:41 AM

Before you start throwing parts at the problem and tearing into the engine, etc., get the code read now that a check engine light is on and see what it tells you.

Len

Carleton Hughes · #3 08-08-2006, 09:50 AM

Quote:

Originally Posted by sokoloff

Before you start throwing parts at the problem and tearing into the engine, etc., get the code read now that a check engine light is on and see what it tells you.

Len

Now that's great idea. since I cannot drive the car where could I rent/borrow a code scanner?

DieselAddict · #4 08-08-2006, 01:06 PM

You may be able to get the code read at Auto Zone for free, but I'm not sure if they still do that. These part stores also sell code readers so that's always an option. Have you inspected the car for fuel leaks, particularly around the IP, fuel filter and injectors? I don't think your car has the intake manifold flaps like the non-turbo cars do. Another thought is the MAF sensor, but you want to confirm that's the problem via the code reader before buying a new one.

Carleton Hughes · #5 08-08-2006, 01:38 PM

Quote:

Originally Posted by DieselAddict

You may be able to get the code read at Auto Zone for free, but I'm not sure if they still do that. These part stores also sell code readers so that's always an option. Have you inspected the car for fuel leaks, particularly around the IP, fuel filter and injectors? I don't think your car has the intake manifold flaps like the non-turbo cars do. Another thought is the MAF sensor, but you want to confirm that's the problem via the code reader before buying a new one.

Well, here's the deal so far. Got the intake manifold off after 15 minutes,not much goop,Resonance valve{sic}on the underside was coked up a little but opened with a mityvac,cleaned it anyway,EGR linkage under the turbo?moves easily and responds to vacuum.

The only fuel leaks are from several return hoses on the injectors leaving puddles of fuel in the injector wells,would this throw off fuel pressure or allow air to enter?
There is a little fuel weeping from some fittings on the side of the IP,O rings,I suppose,dealer part?
There is some sort of solenoid air control valve under the air cleaner which has a vacuum line to the EGR,this was loose off it's mounting and dirty,it has continuity though,what is it?
I would take it somewhere to get it scanned but it won't go for more than a mile now before it acts up and will not accelerate.
How would the K-40 relay,TPS and particularly MAF sensor contribute toward the symptoms I described above.

DieselAddict · #6 08-08-2006, 02:23 PM

You definitely need to take care of those fuel leaks. I'd start with the injector hoses as those are easy to do. The delivery valve o-rings, assuming that's the source of the IP leak, most likely wouldn't cause this sort of a problem but should be addressed eventually. However if it is the shutoff valve or its seal that's leaking (the black box on the side of the IP) then it could very well be causing or at least contributing to this problem.

I don't think it's the K40 relay because in my experience a bad one would cause sudden engine shutdowns instead of rough running. I don't know about the MAF sensor as my car doesn't have one, but I believe yours does and if it is bad it could be causing the K40 relay to mismanage the fuel delivery. First, though, I'd take care of the leaks. I assume your fuel filters are fairly fresh and your prefilter o-ring seals well, otherwise they could be the problem too.

deltajetfixer · #7 08-08-2006, 02:25 PM

Quote:

Originally Posted by Carleton Hughes

Well, here's the deal so far. Got the intake manifold off after 15 minutes,not much goop,Resonance valve{sic}on the underside was coked up a little but opened with a mityvac,cleaned it anyway,EGR linkage under the turbo?moves easily and responds to vacuum.

The only fuel leaks are from several return hoses on the injectors leaving puddles of fuel in the injector wells,would this throw off fuel pressure or allow air to enter?
There is a little fuel weeping from some fittings on the side of the IP,O rings,I suppose,dealer part?
There is some sort of solenoid air control valve under the air cleaner which has a vacuum line to the EGR,this was loose off it's mounting and dirty,it has continuity though,what is it?
I would take it somewhere to get it scanned but it won't go for more than a mile now before it acts up and will not accelerate.
How would the K-40 relay,TPS and particularly MAF sensor contribute toward the symptoms I described above.

I'm fairly certain since you have a turbo model that you don't have resonance valves. I believe the device you saw and cleaned was the EGR valve under the charge air distribution manifold. The device you actuated on the turbo is your wastegate.

You can get a decent code reader at Wal-Mart for @ $100. Try that FIRST. We'll tell you what the codes are. The TPS and MAF will show up here if at fault.

SECONDLY, I would suggest fixing ALL fuel leaks. I'm not Guru enough to know whether the fuel return lines between the injectors can cause the problems you describe but I know leaks in the clear plastic lines will ruin your day. The cotton braided hose for the return lines is available from Phil or from The Stealer at a premium. You'll need MB hose as the return nipples on the injectors sit in a counterbore which necessitates a small OD on the hose so it bottoms out on the nipple barb.

If your IP is weeping fuel from the black box (fuel shut off valve) on its left side, it's most likely the o-ring. Some folks have discovered the valve itself to be leaky but this is rare. If you're getting weeping from around the fuel delivery valves on top of the IP, we can turn you onto the fix there as well (o-rings and a splined socket you'll need to replace them).

You have a nice vehicle. Get the codes read and we'll go from there.

Carleton Hughes · #8 08-08-2006, 02:30 PM

Quote:

Originally Posted by DieselAddict

You definitely need to take care of those fuel leaks. I'd start with the injector hoses as those are easy to do. The delivery valve o-rings, assuming that's the source of the IP leak, most likely wouldn't cause this sort of a problem but should be addressed eventually. However if it is the shutoff valve or its seal that's leaking (the black box on the side of the IP) then it could very well be causing or at least contributing to this problem.

I don't think it's the K40 relay because in my experience a bad one would cause sudden engine shutdowns instead of rough running. I don't know about the MAF sensor as my car doesn't have one, but I believe yours does and if it is bad it could be causing the K40 relay to mismanage the fuel delivery. First, though, I'd take care of the leaks. I assume your fuel filters are fairly fresh and your prefilter o-ring seals well, otherwise they could be the problem too.

I am doubtful of the pre-filter anyway so have ordered a new one as mine varies from dark brown to black,although there is no visible leak,cheap insurance.
I have not experienced any shutdowns,just the lack of acceleration which is permanent now,anybody RENT code scanners???otherwise i'm fumbling in the dark,I suppose.

F18 · #9 08-08-2006, 02:41 PM

Carleton,
I agree with Len and DieselAddict.....you need to read the code!
Buy a code reader, you can get an inexpensive one for under $50.oo these days. It will more than pay for itself with the first diagnostic..... The OBDII codes can direct you to the faulty system or sometimes to the actual defective part.....it takes most of the guess work out of touble shooting the problem. Its well worth the investment now and especially if you are planning on keeping the E-300TD for a while.
Cheers,

Carleton Hughes · #10 08-08-2006, 02:47 PM

I'm there dude.
As I intend to keep the car$50.00 or $100.00 is nothing but a necessary tool I will probably need with increasing frequency as the years pass.
By the way,before I go searching,any particular model of code reader?dedicated for certain models?or what.

Carleton Hughes · #11 08-08-2006, 02:52 PM

http://www.amazon.com/gp/product/B0007LEG2K/103-9005677-1724642?redirect=true

F18 · #12 08-08-2006, 02:59 PM

Quote:

Originally Posted by Carleton Hughes

I'm there dude.
As I intend to keep the car$50.00 or $100.00 is nothing but a necessary tool I will probably need with increasing frequency as the years pass.
By the way,before I go searching,any particular model of code reader?dedicated for certain models?or what.

They are all about the same as long as they are or have the OBDII code reader protocols.
I have the Actron PocketScan that I use on my 98 E-300TD. I bought it at Auto Zone (because it was conveniently close)...I think I paid $59.99 for it. It also allows me to reset or erase the code after the repairs are made.
All vehicles after 1996 have the universal plug for these code readers under the drivers side dashboard.
Good Luck diagnosing the problem...let us know how you made out.

Cheers,
FRED

deltajetfixer · #13 08-08-2006, 03:01 PM

Quote:

Originally Posted by Carleton Hughes

http://www.amazon.com/gp/product/B0007LEG2K/103-9005677-1724642?redirect=true

Yep. Looks like a good deal. OBDII compliant is what you need.

sokoloff · #14 08-08-2006, 03:34 PM

You probably will eventually want to get your own code reader at some point. But for now, you may just want to see if a code reader is one of the tools that Autozones, etc. loan out for free. If so that will get you the codes and give you time to do some searching for exactly the right code reader for your needs.

Len

shoe · #15 08-08-2006, 03:47 PM

You will probably not want to get a vehicle specific reader one that will read manufacturer specific codes will be thousands of $$$$$$$ just get the one you had the link for and it will do everything you will need. I purchased the software from Ease Diagnostics it loadsonto any pc or laptop and will read generic codes. They also sellone that will read Mercedes specific codes but it was $3K I think I paid a hundred or so and I can read some sensor information too.