99 W210 gear shifting problem

I have had the scan done that shows all sorts of issues with transmission, such as gear not shifting, comression not right etc. Can provide spefic codes if someone has a suggestion. I am having intermittent problem of gear not shifting to higher gear 'in the mornings' and is especially is a pain when it just 'shifts' to neutral on its own. If you change gears at that time, the gear lever shifts but the car remains in neutral. If you turn the switch off and on, the gears shift right and you can go for hundereds of miles without having the same problem again during the day. Lately I have noticed that the compression is low as well as the car seems to be making a lot of effort to move, 'in the morning' only. I showed it to a mechanic who was cleless, and could not reproduce the problem on test drive. Does anyone has any ideas because I dont want to be forced to change transmission when it just might be some other proble/reason for this behaviour. Any suggestions are welcome. Thanks in advance.

Reply to
pedro
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Sounds like low fluid level. Whar diagnostic codes are you pulling out of the car?

Cold morning means gear stay longer until the car warms up.

Reply to
Tiger

Thanks for the quick response. The codes that came up are follows:

065-control module 110-RPM compression N2 to N3 implausible 116-TR oil temperature sensor start 135-Can communication disturbed 146-Inadmissible transmission ratio 147-Gear implausible or transmission slipping
Reply to
pedro

What is the current mileage of the car? It does sound like low fluid level... so when is the last time it was serviced? Fluid and filter?

Reply to
Tiger

Is your mechanic a Mercedes specialst or just a general mechanic? Diagnosing an electronic 722.6xx transmission is best done on an MB Star Diagnostics computer system. It can do a lot more diagnostics that can narrow things down compared to a Snap On scanner or whatever.

Another idea is that you could be experiencing the somewhat common transmission connector failure/leakage and the fluid has wicked up to the harness to the tranmission control unit and is contaminating the electronics. This problem is showing up quite a bit on the 722.6xx transmissions now. If you catch it fast enough before the TCU gets fried, you can save it.

Reply to
-

That is true of the electrical harness problem... the fluid travels up to the transmission computer and ruin it.

Reply to
Tiger

I took it in to an MB specialist who replaced the connector plate in transmission. The fluid level was also low, so he flushed and replaced with the lectronic fluid you mention. The harness had no oil on it so I suspecting that the plate may not have been the problem, just the fluid level. I paid $650 for the job and walked away feeling that I paid too much. I have my doubts if the plate was needed to be replaced but oh well, atelast I am not having the problem anymore. Replaced the gasket so that the fluid doesn't leak anymore. Mechanic told me that the fluid was supposed to have lifetime life.but what can be done if there is a leak. Should I go back to the same mechanic next time? Thanks Tiger and all for quick response, you guys rock and know your stuff.

Reply to
pedro

The MB tranny fluid is really a killer... I think youpaid around $28 a quart. Take a look at your receipt. I think that is typical cost of this kind of service. If he did the job right, then he is being good to you.

Reply to
Tiger

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