1992 Mercedes 300 TE wagon - 150k miles

Symptoms:

1. When cold the transmission delays shifting and then shifts hard. Once warmed up it shifts perfectly with no slipping

2. When putting in reverse - cold or warm it takes a long time to engage - up to a minute. Once in gear it works fine. The time to shift into gear Revving the engine the car moves slowly and then catches and works fine. Each time it is shifted into reverse it takes the same amount of time to engage.

The Mercedes Dealership says I need a new transmission. This has been confirmed by a couple of transmission shops. Is there any other options and where can I get a rebuilt transmission?

One other issue the Engine Check light came on at 150K miles. Is there a way to turn it off.

Thanks

Dan

__________________
Project Smoker, '87 603 powered wagon
Hauler, 96 CTD can you say torque?
Toy 73 Cougar xr7 convertible
Acme Automotive Inc.
Raleigh NC
919-881-0364

1. Some aspects of this are normal. These transmissions hold second gear for a while after a cold start.

2. Have you checked the fluid level?

3. Check the archives for how to deal with a check engine light. You're in the 'lucky' group that has a button and LED to tell you what's going on.

Maybe it's a semantic thing but why do poeple ask how to turn off a check engine light rather than what caused it? Turning off the light doesn't make a problem go away.

Sixto
95 S420
91 300SE
87 300SDL
83 300SD

sixto,

Thanks for the help on the light. Since it came one almost exactly at 150K miles and since the car is running perfect except the reverse gear thing I assumed the light was mileage oriented.

But while on the subject I do have a pinging problem. I use the best grade of gas and still the car will ping from time to time when climbing a hill. recently I have not noticed any pinging.

Since the trans is bad the engine also leaks some oil between the block and head. How much of a job is it to pull the entire engine and trans and then replace the head gasket with the trans while I have it all out? Do I need any special tools? If so where can I get them.

Instead of just the head gasket at 150K miles am I better off putting in a rebuilt head or a rebuilt short block. Adsit has a good price on both. Is Adsit a good place for rebuilt parts??

I have many years of wrenching espericence, have a shop with lift and cherry picker and work on my Porsche 928 to keep it running (not a trival task).

To check for codes, locate the X11 port. I think it's somewhere along the firewall in your TE. There's a port with a rectangular flip top cover. With the key to on, engine off, press the button for 2 seconds then count the flashes of the LED. Press the button for another 2 seconds and count the flashes. The codes will display in flashes in ascending order then repeat. To erase the codes, display the code then hold down the button for 10(?) seconds. You have to do this for each code to be deleted.

One of the built-in safety features of computerized engines is that they retard timing when a fault is detected. That might be why there hasn't been pinging since the check engine light came on. Could be a thousand other reasons. If you've had an oil consumption problem for a while, the deposits in the combustion chamber could be contributing to pinging.

Pulling the engine and transmission is a big job, much bigger than dropping the transmission and pulling the head. The lower half of these engines is near bulletproof. I wouldn't touch it just because it has 150K miles.

You can leave the manifolds in the car when you pull the head. It's usually cheaper to have a valve job done to your otherwise good head than to get a rebuilt head, without factoring in convenience.

Consider a new timing chain, tensioner and guides while the head is off. The in-line engines are much easier on the timing chain with fewer direction changes than in V8 engines but it's an opportunity. So with the water pump.

I can't advise you with the transmission. I don't know how tight a W124 transmission hump is. There's access galore in a W126.

Sixto
95 S420
91 300SE
87 300SDL
83 300SD

sixto,

Thanks for the info on the codes. That was easy enough.

I pushed the button and the light blinked 16 times. There was no other codes from whan I can tell. I pushed the putton and held it for 10 seconds and now the engine check light is off.

I did a search on the forum and could not find any place the codes are listed. I checked the CD I bought for the car and there do not seem to be any codes listed there either. Any place the codes are to be found? This is a 92 300 TE wagon.

Your suggestions on the engine and trans are appreciated. I was thinking since the trans is bad and the pull procedure in the book does not look so bad it might save time working on the bench rather then under the car.

A head exchange from Adsit is about $300. I doublt if a shop locallay could do a rebuild on the head with guides for any less. Any other suggestions other than Adsit for quality parts at better prices.

With pulling the head and changing the timing chain do I need any special tools. I know every time I do a new job on the Porsche I have to get some new wrench or something.

Is pulling the engine, changing the trans and putting on a new head a three day job if all of the parts are availabe at the time. I have a helper for the heavy stuff and air tools.

Thanks again for all your help.

About the only special tool you need is a 12-pointed bit tool that's driven by a 1/2 socket to remove the head bolts. Fancy versions that match MB specs are available but I find that the PepBoys or AutoZone 4-pack (6mm, 8mm, 10mm and 12mm) for less than $12 fits the bill. I believe that the M103 uses the 12mm bit and you'll have the 10mm when you see the light and upgrade to a car with an OM601/2/3 series engine You can also spring for the slide hammer arrangement to extract the timing chain guide rail locating pin/s but I've had good luck stacking washers on a high grade bolt to extract the pins. The tool I wish I had is the rod that holds the fan clutch steady for removing the 8mm allen head bolt on the fan. I use some thick wire that eventually catches the notch properly. I've told myself, "this is the last time I'm removing this fan" the last 20 times I've taken off the fan so you'd think I'd learn. Oh, there's a stubby 8mm hex tip tool that fits in the gap between the fan and the radiator. In my 300SE there's enough room to fit an 8mm hex key driven by a 10mm deep socket and breaker bar.

I don't know what tools you'll need to rebuild the transmission.

I still think it's easier to drop the transmission and pull the head than rip everything out.

www.adsitco.com has a rebuilt 103.983 head for $900. How do you figure it's $300?

Sixto
95 S420
91 300SE
87 300SDL
83 300SD

Sorry, I did my math worng - too late at night. I was subtracting the core from the price.

If I just pull the head and install a new gasket is this viable on a 150K mile car. It really does use a bit of oil and make a mess on the floor. It has not got any worse from when I got the car at 86K miles, so I am tempted to live with the leak for a while longer. Oil usage is about a quart in 700 miles.

Lately the car has started to use a little water. I assume from the same palce since I can not locate any other leaks. About a quart in 1500 miles.

If I was going to do any upgrading I would put in a diesel engine. I really miss my 190D with its 38 MPG. 225K when I sold it with a bad heater. Now pushing 300K with the engine going strong - although now it needs a trans too. Pint and interior still look great and the car still drive like new.

If all that is required is a star socket then it is not a big deal - I have one of them.

You did not mention a source of the engine codes.

Thanks again.

I found this list at another forum...

> 1 NO MALFUNCTION IN SYSTEM.
> 2 FULL LOAD CONTACT THROTTLE VALVE SWITCH.
> 3 COOLANT TEMPERATURE IN CIS-E CONTROL.
> 4 AIRFLOW SENSOR POSITION INDICATOR POTENTIOMETER.
> 5 02 SENSOR SIGNAL.
> 6 not used
> 7 TD/TNA SIGNAL (RPM SIGNAL) AT CIS-E CONTROL UNIT.
> 8 ALTITUDE CORRECTION SIGNAL FROM EZL/AKR CONTROL .
> 9 CURRENT TO ELECTROHYDRAULIC ACTUATOR (EHA).
> 10 IDLE SPEED CONTROL THROTTLE VALVE SWITCH.
> 11 AIR INJECTION SYSTEM.
> 12 EXHAUST GAS RECIRCULATION (EGR); ABSOLUTE PRESSURE VALVE FROM EZL/AKR CONTROL.
> 13 INTAKE AIR TEMPERATURE.
> 14 SPEED SIGNAL AT CIS-E CONTROL.
> 16 EXHAUST GAS RECIRCULATION (EGR).
> 17 02 SENSOR SIGNAL WIRE IS SHORTED TO POSITIVE OR GROUND.
> 18 IDLE SPEED AIR VALVE CURRENT.
> 22 02 SENSOR HEATER VOLTAGE.
> 23 SHORT TO POSITIVE IN REGENERATION SWITCHOVER VALVE.
> 25 SHORT TO POSITIVE IN START VALVE CIRCUIT.
> 26 SHORT TO POSITIVE IN TRANSMISSION SHIFT POINT CONTROL VALVE.
> 27 DATA EXCHANGE CIS-E CONTROL UNIT EZL/AKR IGNITION CONTROL UNIT
> DEFECTIVE.
> 28 INTERMITTENT CONTACT IN COOLANT TEMPERATURE SENSOR.
> 29 DIFFERENCE IN COOLANT TEMPERATURE BETWEEN CIS-E CONTROL UNIT
> EZL/AKR
> IGNITION CONTROL UNIT.
> 31 INTERMITTENT CONTACT IN INTAKE AIR TEMPERATURE SENSOR.
> 32 INTERMITTENT CONTACT IN REFERENCE RESISTOR.
> 34 COOLANT TEMPERATURE FROM EZL/AKR IGNITION CONTROL UNIT.

[search keywords for future reference - 300e m103 dtc engine fault code codes]

Sixto
95 S420
91 300SE
87 300SDL
83 300SD