99 e300 weird problems need help!!! - PeachParts Mercedes-Benz Forum

pnolet · #1 09-26-2012, 03:29 PM

Hi there,

I have a 99 e300 turbodiesel with 295k. I love the car but I've been chasing fuel problems for a year....I'm at a loss. So I figured I'd throw it out tithe world of master mb minds. Thanks n advance.

So starting a yeAr ago I noticed air in the lines. Naturally I started with replacing filters and all the old hard lines under the hood. The bubbles mostly went away, except a few minor bubbles. I started also experiencing a major nail at idle, and at almost 300 I had the injectors serviced. I reinstalled them wi new crush washers. The problem is still happening but with added symptoms. Before the injectors service I had bad turbo lag, and it's been getting worse, after injectors, there's no difference. Now my newest problem when it gets below 1/4 tank it gets a ton of bubbles and dies. I'm guessing tank?

Also a little puddle of diesel/oil on the ground sometimes. I've replaced the dv seals, all the lines and lines to the injectors, the fuel thermostat (because I broke it) the sob o ring and the egr o ring. What else should I look for? The bottom of the ip is wet when I clean it It just gets wet again, but I can't pinpoint it. I need help I want this car back to normal, I hate driving it like this

Zulfiqar · #2 09-26-2012, 03:43 PM

This sounds like a classic case of blocked fuel tank strainer. If this was a W124 the tank strainer is reached from under the car above the differential and unscrewed with a 46mm socket or a toilet wrench. It can be reused - just clean out the gunk from it with a good strong surfactant and hot water. I beleive this same job in the W210 is a pain as the strainer is a little to the side.

For the diesel leak, clean out the pump with simple green and water, then apply a hair dryer to it, take a light bulb of the highest luminosity you can get, start the engine and look for the leak. I have seen a post here showing the shutoff valve O ring going bad and leaking fuel slowly.

TMAllison · #3 09-26-2012, 04:11 PM

Find the line in the attached fuel path where bubbles first appear, and work backwards from that point. fuelflow.JPG (image)

Because everything prior to line 4 is under suction, that is where you will usually find air leaks with fuel leaks from line 4 on where everything is pressurized.

After 14 years some of the rubber hoses from the tank up to the fuel thermo could be deterioating.

I've had issues getting the prefilter completely sealed. Had to crimp the hold down washer to get more downward force to stop a small air leak. Prefilters can crack and fail also.

I'd waste a can of carb or break cleaner on the fuel filter housing and IP and then move the windsheild washer bottle, fire it up and reach under and feel for wetness.

pnolet · #4 09-26-2012, 04:55 PM

The strainer was my next try. Tank access on the w210 is in the trunk since I can't run the car all the wAy empty I have to change it with a quarter taankq.. What's the easiest way to change it for me?? I'll also clean the ip. I've replaced the shut off valve and oring also. I'm beginning to think the ip just leaks but i just don't know and that's an expensive "guess". Im in Oklahoma for school but live in Houston. Are there any people near meaning anywhere in ok, tx or surrounding states that just really knows this engine, and would be willing to help me with pay of course? I'm also happy to drive especially if my drive backhome is potentially more enjoyable. I miss th way this car used to drive

Zulfiqar · #5 09-26-2012, 06:57 PM

If the DV O rings are replaced and you are sure the pump is not leaking then the most obvious point is the fuel O rings and your version of the OM606 has the electronic thing that moves the rack - It has an O ring that can leak.

For the tank strainer - suck out the quarter tank of fuel and remove the strainer, My guess is that its pretty packed up with slime.

KarTek · #6 09-27-2012, 06:48 AM

Some things to watch out for when doing the strainer:

The fuel fitting has to come off to use the big socket to remove the strainer. The fitting was frozen to the strainer so I had to cut the hose off to make it possible to get a socket on it. Then, I had to order a replacement hose and wait for it to arrive before I could put the car together again.

The fuel fitting was stuck so badly that the entire strainer actually loosened just from the force I was putting on the fitting!

For draining the tank, you can remove the short, 10" section of hose that runs from the strainer to the hard fuel line at the tank and direct it into a smaller container to get the last couple gallons out. I took small vise grips and pinched the hose flat to act as a valve when I needed to empty the container.

My tank had about 2" of black poo in the bottom and I had run out of fuel twice at around 1/4 tank.

Oh, and one last thing: A common mistake is to place the SOV o ring all the way up against the body of the valve rather than against the step in the tube that inserts in the the IP body.

hobbitss · #7 09-27-2012, 09:45 PM

Check the rubber fuel line that comes up the fire wall. Where the metal fuel line is attached the rubber may have dried out and is leaking... My 98 E300D had a similar issue a couple of years ago and the Indie that works on my brother's 98 E300D simply cut a couple inches off of the rubber hose and re-attached the metal tube... The stumbling disappeared after a couple of days of normal driving...
If you haven't had your Intake manifold cleaned out, that will make a big difference in performance...

pnolet · #8 11-13-2012, 03:13 PM

I finally got the time to button her up and get it goin again.i finished the strainer with a new fuel hose that attaches to it. I also replaced the fuel filters. Now I got it started drove it with less than a quarter tank for about 4 minutes and it died. Ran home got the ford and towed her back home. Got it started in the driveway after a lonnngggg crank. All the lines had massive bubbles and it ran like S**t. No I'm stuck again. What is my next step? The strainer wasn't clogged at all.

anghrist · #9 11-13-2012, 03:27 PM

These two previous posts should solve most of your problems. I would do as described, and find any wet spots first, then move on to upstream troubleshooting for the introduction of air into the system.

Quote:

Originally Posted by TMAllison

Find the line in the attached fuel path where bubbles first appear, and work backwards from that point. fuelflow.JPG (image)

Because everything prior to line 4 is under suction, that is where you will usually find air leaks with fuel leaks from line 4 on where everything is pressurized....

....I've had issues getting the prefilter completely sealed. Had to crimp the hold down washer to get more downward force to stop a small air leak. Prefilters can crack and fail also.

I'd waste a can of carb or break cleaner on the fuel filter housing and IP and then move the windsheild washer bottle, fire it up and reach under and feel for wetness.

Quote:

Originally Posted by KarTek

...Oh, and one last thing: A common mistake is to place the SOV o ring all the way up against the body of the valve rather than against the step in the tube that inserts in the the IP body.

Once you find the culprit of the air bubbles (just the major source, you might not get rid of all air bubles), then go ahead and invest in a few extra fuel filters and some diesel purge, you will use them sooner or later anyhow. A diesel purge shouldn't hurt things and might give you back a little mileage and performance.

anghrist · #10 11-13-2012, 03:30 PM

Quote:

Originally Posted by KarTek

...My tank had about 2" of black poo in the bottom and I had run out of fuel twice at around 1/4 tank....

That's not what you're supposed to put in the diesel tank.

Has a similar problem with the W123, but it was some other sort of black goo. I wouldn't think that this problem would be seen on such a 'young' diesel, unless you live in a humid envrionment and let the tank sit on 1/2 to 1/4 most of the time.

seubill · #11 11-16-2012, 08:16 PM

"Oh, and one last thing: A common mistake is to place the SOV o ring all the way up against the body of the valve rather than against the step in the tube that inserts in the the IP body."

I just made this mistake, placing the sov o-ring all the way up next to the body. I'm getting air in the plastic lines and tripped a code "fuel shutoff solenoid malfunction". Question, could this condition be the result of simply having the o-ring up against the sov body, or do I have something else going on?

cullennewsom · #12 11-16-2012, 08:42 PM

It is really easy to nick that o-ring installing it.

seubill · #13 11-16-2012, 08:48 PM

Yes, but wouldn't that o-ring be on the pressure side, not the suction side?

KarTek · #14 11-16-2012, 11:02 PM

The only thing I can guess is that you've warped the plastic body of the SOV by putting the o-ring in the wrong spot. This may be putting the internal mechanism in a bind.

Have you put everything back the way it belongs? If so, it will take 3 cycles of starting the engine cold, warming to operating temp and then shutting off and returning to cold in order to clear the codes.

Of course, you can also clear them manually if you have a scanner.