Bought my first MB today - '90 300TE
Thread Starter
Junior Member
Joined: Jun 2009
Posts: 48
Likes: 0
From: NW Michigan (USA)
'90 300TE (S124)
I believe that the 3rd stoplight bulb needs to be working order for the cruise to work. My W201 190E, developed at the same time, and sharing many of the same components and systems, had this problem. The bulb was out in the 3rd (high level) brakelight. Once replaced, problem solved.
Maybe that's too simple?
Worth a try...
Maybe that's too simple?
Worth a try...
If the engine runs nice...you can always leave it alone...but if you are intent on getting back that power then read on. Also, hows your fuel economy? That can indicate pretty well how the engine is. My wagon runs great, but is massively overfueling for some reason as I get about 13mpg average which is terrible in comparison to my 260E which got almost 23mpg last fill up.
MBWorld Fanatic!
Joined: Jun 2006
Posts: 4,968
Likes: 3
1990 300ce 24v I6
Maybe you do have a bad ground somewhere. Check that all dual-filament bulbs are proper (blinkers), the MBs rely on a good ground circuit and a single filament bulb in the wrong spot can cause ghosts.
MBWorld Fanatic!
Joined: Apr 2007
Posts: 2,381
Likes: 29
E
MBWorld Fanatic!
Joined: Dec 2003
Posts: 1,016
Likes: 0
I believe that the 3rd stoplight bulb needs to be working order for the cruise to work. My W201 190E, developed at the same time, and sharing many of the same components and systems, had this problem. The bulb was out in the 3rd (high level) brakelight. Once replaced, problem solved.
Maybe that's too simple?
Worth a try...
Maybe that's too simple?
Worth a try...
Thread Starter
Junior Member
Joined: Jun 2009
Posts: 48
Likes: 0
From: NW Michigan (USA)
'90 300TE (S124)
I found a CC amp on eBay, installed and it is working great! Easy fix for only $45. 
Thanks for all the advice. Next up is changing the transmission fluid and filter and see if it will shift any smoother.
1,500 miles so far, including a camping trip. I have had wagons before and I am still surprised I could fit a bicycle, all camping gear, cooler inside and a kayak on top. It has been a comfortable car for longer distances, even though I could really have used CC on that trip. I guess I have to take another trip soon.
Few more here of the Michigan U.P.: http://wulfers.net/pictures/michigan4/index.html
Thanks for all the advice.
Next up is changing the transmission fluid and filter and see if it will shift any smoother.1,500 miles so far, including a camping trip. I have had wagons before and I am still surprised I could fit a bicycle, all camping gear, cooler inside and a kayak on top. It has been a comfortable car for longer distances, even though I could really have used CC on that trip. I guess I have to take another trip soon.
Few more here of the Michigan U.P.: http://wulfers.net/pictures/michigan4/index.html
MB World Stories
The Best of Mercedes & AMG
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
Thread Starter
Junior Member
Joined: Jun 2009
Posts: 48
Likes: 0
From: NW Michigan (USA)
'90 300TE (S124)
It was worth it to check into. You just never know what could be causing the problem.
One thing I was wondering about... what's with the different size and shape of the left and right rear view mirrors? I imagine there must be some reason but I haven't figured it out yet.
One thing I was wondering about... what's with the different size and shape of the left and right rear view mirrors? I imagine there must be some reason but I haven't figured it out yet.
Thread Starter
Junior Member
Joined: Jun 2009
Posts: 48
Likes: 0
From: NW Michigan (USA)
'90 300TE (S124)
7,000 miles and counting. I have done the following service so far.
Air filter $15.75
Oil and filter Valvoline Max-Life Synthetic Blend 10W-40 $32.00
Transmission fluid/filter - Valvoline Max-Life DEX/MERC $42.85
Spark Plugs - Bosch Yttrium HR9DC $9.60
Antenna mast $16.58
Fuel Filter - Bosch $13.41
Serpentine Belt - Continental $24.98
Transmission fluid change $24.00
Coolant change $13.72
Brake rotors and pads (front) $134.65
Total $327.54
How much would a MB dealer charge for all of this, including labor?
It's an easy car to work on and it just takes time to get familiar with it. I was doing my front brakes this evening and it took me 2 hours to do one side and 20 minutes the other.
I ordered some used Hella headlights in Germany and will have those in January after my visit there. That'll be a nice change to the car as well. The car is a joy to drive and I never feel like it will leave me stranded somewhere.
I have done the following service so far.Air filter $15.75
Oil and filter Valvoline Max-Life Synthetic Blend 10W-40 $32.00
Transmission fluid/filter - Valvoline Max-Life DEX/MERC $42.85
Spark Plugs - Bosch Yttrium HR9DC $9.60
Antenna mast $16.58
Fuel Filter - Bosch $13.41
Serpentine Belt - Continental $24.98
Transmission fluid change $24.00
Coolant change $13.72
Brake rotors and pads (front) $134.65
Total $327.54
How much would a MB dealer charge for all of this, including labor?
It's an easy car to work on and it just takes time to get familiar with it. I was doing my front brakes this evening and it took me 2 hours to do one side and 20 minutes the other.
I ordered some used Hella headlights in Germany and will have those in January after my visit there. That'll be a nice change to the car as well. The car is a joy to drive and I never feel like it will leave me stranded somewhere.
Last edited by Wulf; Oct 20, 2009 at 10:50 PM.
Love the color. 
MBWorld Fanatic!
Joined: May 2007
Posts: 1,450
Likes: 1
From: British Columbia, Canada
1987 560SL
Left mirror is closer to the driver so does not need to be as big.
MBWorld Fanatic!
Joined: Apr 2007
Posts: 2,381
Likes: 29
E
You Are running resistor plugs so I'd recommend swapping those out. Next oil change make sure to be using a diesel grade oil as the one you are running is not best as it does not have the zinc additives that this engine likes. Without them there will a little more wear on the cams etc. Delvac, rotella or mobile 1 super 1300 are the correct oils to use.
Thread Starter
Junior Member
Joined: Jun 2009
Posts: 48
Likes: 0
From: NW Michigan (USA)
'90 300TE (S124)
The HR9DC plugs are a direct replacement for the H9DC plugs. They showed up for my car on autohausaz.com and also on the Bosch website.
Since the H9DC are not made anymore, which ones are the recommended type for the M103? The engine runs great with these plugs.
Since the H9DC are not made anymore, which ones are the recommended type for the M103? The engine runs great with these plugs.
MBWorld Fanatic!
Joined: Apr 2007
Posts: 2,381
Likes: 29
E
NGK BP6EFS
Champion S12YCC
For H9DCO, you can try special order over at PP
http://catalog.peachparts.com/item.w...sku=0031590403
I heard you can buy the zinc+phosphate additive to put into your current oil if you want to stick with it.
Your father’s motor oil may have been old reliable, but it may be time to move on. It’s more than a coincidence that engine builders have experienced more flat tappet cam failures in the last few years than at any point prior. And that’s because today’s engine oil has a lower amount of anti-wear additives than your flat tappet cam requires in order to keep it spinning freely.
Experts say that the reasons behind the changes in engine oil are numerous, but one of the main reasons is that the American Petroleum Institute (API) has regulated the amount of zinc levels to .08 percent, down from .15 of a few years ago (and even higher levels before that) due to its harmful effects on catalytic converters and emissions systems.
Experts say that the reasons behind the changes in engine oil are numerous, but one of the main reasons is that the American Petroleum Institute (API) has regulated the amount of zinc levels to .08 percent, down from .15 of a few years ago (and even higher levels before that) due to its harmful effects on catalytic converters and emissions systems.
Last edited by ps2cho; Oct 21, 2009 at 06:11 PM.
