S.O.S.-At the mercy of my trans. Begging for help. W124, 1986, 300E - PeachParts Mercedes-Benz Forum

appatula · #1 07-06-2007, 09:37 AM

Hello all I'm going to break this down for you to make things a tad bit easier.

Situation: I am 17 and heading off to Penn State U. come august. I bought a 1986 300E and started to recondition it to serve as my transportation in Pennsylvania.

What I did:I started off by replacing the front lower control arm bushings, tie rods, strut mounts, ball joints, rear differential mounts, fluid changes ect. However when this was done I was still finishing my senior year in high school. The car sat in the garage dismantled for quite some time before I was able to complete the project.

The Problem:
Upon starting the car up for the first time I was in my glory, proud of my hard work. She backed out just fine, shifted into first and sped off. I slowly accelerated away from the front of my residence. Then my heart slowed, I noticed that the RPM's where above 3k, this then turned into 4K and at 4.3K I let off the gas and BOOM second gear slammed in. This happened through 3rd gear and at times the car would not shift into 4th. At times when the car will not shift I have found that manually shifting the gear selector to "N" then "D" sometimes will create an up shift.

Attempted Remedies:
1] I have inspected all sensor connectors and wires underneath the transmission.
2] Replaced the vacuum line from the intake manifold to the trans.
3] Performed a complete fluid change with Valvoline Dextron III & Filter

Cries for Sympathy:
At this point I do not have much cash left, I am leaving soon, and if this car stays where it is the result will simply be the junkyard. However this damn car has caused me such grief and madness, I really do not wish to give up, I have spent too much money and time. Basically I need help, suggestions, and to be pointed in the right direction as my morale is running wickedly low.

Thank youMB enthusiasts.

brewtoo · #2 07-06-2007, 09:50 AM

The bowden cable controls when the trans shifts, but I can't imagine anything could have happened to it while it sat. Perhaps something gummed up in the valve body while it was sitting. How long did it sit?

appatula · #3 07-06-2007, 10:42 AM

I would say over a month, less than two. What shall I look for/feel for on the bowden cable?

david s poole · #4 07-06-2007, 11:15 AM

when was last time trans had service?have you checked fluid level with engine running?what is color of fluid?get new fluid ,put some on back of hand,then pull out trans dipstick and put fluid on hand next to new stuff and compare.

appatula · #5 07-06-2007, 12:05 PM

Yes, not have I only checked the fluid with the engine running, but after driving it for some time (warming up the gearbox) The fluid I flushed from the pan and torque converter seemed to look just like the new fluid I put back in. No pungent smells either.

Dammit.

david s poole · #6 07-06-2007, 02:07 PM

ok you say it only sat for two mths which is not really enough time for bad fluid to play nasty with the seals.so the problem almost has to be one of three things.dirt in the valve body[which might be moved by just driving] bad modulator diaphram[which can be checked from the intake manifold connection with hand held vacuum pump] or a broken spring in the valve body above the valve that is moved by the bowden cable[this can be checked by disconnecting the cable at the throttle linkage and pulling on it by hand to make sure of the spring pressure to return it to the original position].

appatula · #7 04-11-2009, 12:18 PM

Not trying to dip up an old thread, however, I did fix the problem. It turns out that we were all overestimating the complexity of the problem, the kickdown switch had failed. All has been well since.