The wife's E320 wagon (122k miles) looks like it needs new engine mounts (getting some vibration while in reverse, "solved" by putting just a bit of lift on the front of the engine). A couple questions:

1) My quick peak suggests that access to the mounts will be from the bottom - is it as simple as pulling the underbody tray and there they are? Any pointers?

2) Fastlane shows two different mounts - Lemforder @ $91 (each, I assume - this brand is listed as left:right?) and no-name @ $134 each right/left. Other than the $43 per price delta, any meaningful difference between these two? Anybody know who makes the un-branded (and more expensive) version?

Thanks -

I can't help you with the parts information, but on either E320 (m104 or m112 powered), it should be pretty straightforward from underneath. You'll see everything layed right out in front of you. Loosen them both, but only remove one at a time. Not a tough project, but it can get a little frustrating lining the bolts back up. Good weekend project.

One of my books suggests you have to carry out a sensor gear adaptation if you change the motor mounts (along with flywheel/ring gear replacement, crank sensor replacement, and ECM), although I do not yet know why.

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What year 210 do you have (aka what engine do you have)?

He wasn't saying to replace the flywheel and ecm. If i understood him correctly, he was suggesting to perform sensor gear adaptations after replacing the motor mounts like you would IF you replaced the flywheel or ecm.

Exactly, I was saying there are 4 reasons for performing sensor gear adaptations, not 4 things that have to be replaced. This is for '98 and up 112/113 motors, but adaptation for motor mounts, I'm saying I'm not exactly clear why, since I've yet to do it.

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Sorry for that omission - the wagon is a 2001.

Got the parts ordered, turns out the no-name entry in the catalog doesn't exist - the Lemforders are the only thing stocked.

Can you clue me in here? What is a sensor gear adaptation?

Thanks!

My books say to perform a sensor gear adaptation when you change out the motor mounts on a '98 & up M112/113 engines (V6 & V8 engines). Here is the info below:

"Some vehicles have an adaptation procedure to enhance the sensitization and reduce false misfire reporting.

Sensor gear (flywheel) adaptation may be required on ME-SFI 1.0, 2.0, 2.1, and 2.8. Sensor gear adaptation started approximately in 1998 with the ML 112/113 engines. Later ME 2.8 and SIM4 may also use this function. The adaptation re-configures the ME controller for increased sensitivity for misfire detection.

Drive train influences on misfire detection are:

*Crankshaft flex
*Motor mount movement
*Torque convertor lock-up function
*Automatic transmission shift characteristics
*driveshaft and differential vibration

Misfire detection using the crankshaft position sensor requires sensor gear adaptation whenever the following componants are replaced:

*Flywheel or starting ring gear
*Crank sensor (L/5)
*ECU
*Motor mounts

In some cases, sensor gear adaptation must be performed after a misfire code.

The engine is constantly monitered for misfire to protect the catalytic convertor. The engine is analyzed by evaluating the crankshaft position sensor using a sophisticated mathematical method to determine whether precise time synchronism exists between individual combustions. Each individual combustion must prodice a characteristic acceleration at the flywheel. If misfire occurs, flywheel rotation slows slightly. These parameters are the amount of correction the ECU is making to filter out vibration and prevent setting false misfire codes. The ECU sets irregular engine running analysis or misfire detection to a less sensitive setting when driving on a poor road surface. The body acceleration sensor, or electronic vibration module, detects a rough road and sends this information to the ECU. The misfire sensitivity level can also be altered as a functional test. A lower threshold enables the ECU to detect less severe misfires indicated by reading the RPM decrease and misfire fault counter for each cylinder.

The crankshaft sensor gear adaptation mean value reflects the addition of a supplementary correction factor designed to compensate for phase error in the crankshaft sensor. This information is used to compute actual ignition timing. Each segment represents the duration between each new ignition cycle. Ignition, injection and engine speed derived from segment duration are recalculated for each segment."

Hope this helps.

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Don't ask me, I'm a shop-owner by default

Thanks so much for posting that info - now I understand why sensor gear adaptation is potentially needed following mount replacement.

From the content of the text, I'm guessing that the process of adaptation involves a smart/electronic diagnostic tool of some sort - i.e. not something I could do with a timing light & basic tools

Guessing again - sounds like the potential outcome of NOT doing the adaptation would be shortening the lifetime of the catalytic converter?

Any clue what I might expect to spend to have a dealer or good shop do this?