96 E300d - PeachParts Mercedes-Benz Forum

lakerat · #1 01-30-2007, 09:47 AM

I dont no if this is a problem or not but my transmission flares when it shifts from 2 to 3 when it is cold and when your not giving it much pedal it seems like the more pedal you give it the better it shifts? Is this norma or is this a problem with the vaccum controler. Thanks for any info.

TMAllison · #2 01-30-2007, 12:20 PM

Is not normal. I think two trans were used on 96's. Some old style with older vacuum controls and others the first generation of electrical controls.

lakerat · #3 02-23-2007, 09:48 AM

The transmission in my car is the older style vac. operated. The car has about 58,000 miles on it and I am worried about the flaring from 2 to 3 is this bad for the the trans I am still trying to find out why it is doing this, I changed the trans fluid and filter but did not help the problem, it apears to be erratic but does it most of the time when your going slow and the trans. oil is cold once you drive it on the highway and the oil is hot it does not do this ,does anybody have any ideas on this problem. Thanks

TMAllison · #4 02-23-2007, 12:22 PM

Any time it slips it bears looking into. Some of the early trans had valve body problems I think. I dont know if that applies to your. I think it was more the earlier elec controled models.

I would prob have it scanned with SDS to see if there are any trans codes stored. They wont show up as a CEL or using OBDII scanners.

Matt L · #5 02-23-2007, 01:39 PM

Are there any codes in a 722.4?

TMAllison · #6 02-23-2007, 02:17 PM

Quote:

Originally Posted by Matt L

Are there any codes in a 722.4?

Hmmmm...thats a good point Matt. If its the old style trans and not electronically controlled it may not store codes.

Sure is a pain that they switched parts in the midst of a model year.

Regardless, it should be looked at as the flare should not be present.

mdisav · #7 02-23-2007, 05:42 PM

Adjust the vacuum control valve at the throttle position sensor where the accelerator cable attaches in the engine compartment. You will have to rotate it clockwise to get less vacuum and more pressure at the desired throttle position. Keep in mind the vacuum valve is mounted upside down. Rotate it clockwise as if it were right side up.

lakerat · #8 02-25-2007, 12:21 PM

I can see the vac. control valve but I dont see an adjustment on it can someone provide a picture that shows the screw adjustment. Thanks

TMAllison · #9 02-25-2007, 01:29 PM

I believe it is number 90 and that 100 is the adjusting key and 95 the cover on the attacheed diagram.

If it is like the older style modulators you pull on the key (~1/4") and rotate clockwise to increase pressure and firmness of shifts.

Document what you do so you can go back to the factory setting if need be.

http://www.detali.ru/cat/oem_mb2.asp?TP=1&F=210020&M=606%2E912&GA=722438&VIN=%2A&CT=GA&cat=09S&SID=27&SGR=045&SGN=03

mdisav · #10 02-25-2007, 01:53 PM

Do Not adjust the pressure at the modulator on the transmission. If you do you will cause a premature failure down the road. You must adjust the vacuum valve that is bolted to the throttle position sensor in the engine compartment where the accerlator cable is attached. It is two 10mm bolts that are loosened then it is rotated either way to soften or harden the shifts with respect to throttle position.

DieselAddict · #11 02-25-2007, 02:33 PM

Quote:

Originally Posted by mdisav

Do Not adjust the pressure at the modulator on the transmission. If you do you will cause a premature failure down the road. You must adjust the vacuum valve that is bolted to the throttle position sensor in the engine compartment where the accerlator cable is attached. It is two 10mm bolts that are loosened then it is rotated either way to soften or harden the shifts with respect to throttle position.

Regarding the modulator on the transmission and causing damage by touching it, I don't think that's true. It is there to allow a knowledgeable user to adjust the shifting firmness appropriately. I have mine set at about the middle position, not too firm and not too soft. Turn it CW to firm up the shifts. You can't do any harm by doing that, though you could potentially cause premature wear if have your shifts set too soft. BTW, I just looked at the throttle cable area of my engine compartment and I don't see anything there to adjust other than the throttle cable and the bowden cable which controls the timing of the shifts, not their firmness. I have mine set as far back as possible (making it tight) to delay upshifts and it feels about right to me. Lakerat, you might want to do the same if you're saying that your transmission shifts better with more throttle.

mdisav · #12 02-25-2007, 02:48 PM

I agree too hard should not do damage but adjusting the modulator at the transmission when other adjustments can be made else where to soften the shift is not good practice.

Earlier 96's have the same vacuum valve used from 86-95. You must have a later 96 Diesel Addict.

lakerat · #13 05-28-2007, 06:15 PM

I finally fiqured out when this problem occurs. It happens at low RPM it will actually slip a little before shifting to third gear, if you give the car some gas it will shift at a higher RPM with no problems does anybody no what would fix this problem. I have changed the oil with no luck in curing the problem. Would adjusting the modulator help this problem?

mdisav · #14 05-29-2007, 06:44 PM

Please post a picture of where the throttle cable attaches inside the engine compartment on the drivers side close to the firewall.