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  #1  
Old 08-30-1999, 01:20 AM
EricH
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I've got a new to me 500E. Nice car but why does it shift at 4000rpm in first? And that's if I can get it to start in 1st, usually it won't. Isn't it supposed to shift at 6000rmps? Other symptoms are that it is flakey on the downshifts. It often won't downshift at all, and when it does it will only drop 1 gear. If I am cruising at 55mph and want to pass, shouldn't it shift from 4th to 3rd to 2nd? Also I just took my first day trip in the car and got only 16mpg overall. If I were driving about 80-90mph most of the time with A/C, would this be acceptable?

Thanks,
Eric

  #2  
Old 08-30-1999, 02:50 PM
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Join Date: Mar 1999
Location: Atlanta, Georgia, USA
Posts: 1,342
Eric,
Congratulations on your new car. 500E's are too much fun! The 500E is supposed to start in 2nd gear unless your transmission has had some hot-rodding work done to it. The kickdown to 1st is 40% or greater throttle. (or of course clicking the shifter over to first) My 92 500E will spin up to about 6300rpm in 1st gear and a solid 6000rpm in all others. Kickdown to all gears except first can usually be had through 2/3rds of the gear being kicked down into. If you are at 50mph you should be able to get 2nd (which redlines at approx 68mph) The 722.3 tranny is infamous for being a dullard on downshifts. It frequently lugs in a higher gear until you pin the throttle then gives you a rush you wont soon forget. You can either shift manually or get used to it somewhat. You could adjust the Bowden cable to alter shift points somewhat. If your interested let me know and we'll take it from there.

BTW, 16mpg isn't that bad for summer, A/C on, high speed or aggressive driving. My 92 500E gets about 20-22mpg highway cruising (75-85mph and anything from 14mpg to 18mpg in town depending on driving style. The A/C seems to really suck some MPG. I believe the EPA ratings for our cars was 14/17 so if your getting 16mpg then you are doing okay. Its always good to hear from other 500E owners out there. Congrats once again.

Hope this helps...Lee
  #3  
Old 08-30-1999, 07:31 PM
EricH
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Lee, Thanks for the reply. I definitely don't get 2nd at 50-55 mph, and don't always get 3rd upon hard throttle, even when the kickdown or whatever switch under the pedal is closed. Also when starting off from a stop, even if I select 2nd I will only get 4000rpms in 1st before the change.

What's a bowden cable? and would an adjustment help the shifting? Is the downshifting controlled by vaccum? and if so might it be possible that I have a leak somewhere?

Thanks,
Eric
  #4  
Old 08-30-1999, 08:44 PM
Michael's Avatar
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Join Date: Jul 1999
Location: Boston, USA
Posts: 2,701
I thought I'd post the attached, which is an email Lee kindly provided me with that describes the adjustment of the Bowden cable. Good luck....wish I could offer a solution.

"...You want to pull the car out where you have reasonably good lighting.
Then open the hood all the way. (vertical) Look dead center behind the
engine, between the back of the airbox and the firewall. You will see a
cable and beneath the cable, a bolt with two rounded socket ends. The bolt
is what you will be adjusting. Before we take that out look towards the
driver's side past the cable/double ended bolt. You will see two black
plastic pointers with red painted ends. When the Bowden cable is at "spec"
those two red lines/arrows should line up perfectly. By lengthening the
double-ended bolt you raise the shift points and firmness. By shortening
the bolt you slur shifts and lower shift points. Hence, when the arrow
closest to the front of the car is closer to the driver's side fender it is
"more aggressive" adjustment. When the front arrow is closer to the
passenger side fender (than the stationary arrow that is closer to the
firewall) it is "less aggressive" adjustment. I find it easier to brake one
end of the bolt loose from its mounting point and turn the bolt while the
other end is still attached. This may not always work, but it makes "fine
tuning" much easier because you know you are only "1 turn past spec" or
whatever.
To get the bolt off of its points: Spray some WD40 or something on the
bolt as it may be a touch stiff. Then insert a flathead screwdriver between
the mounting point "ball" and the "socket" at the end of the bolt. Twist
the screwdriver to pry it apart/loose. It may not go all the way off, but
you should get it mostly loose. A good jerk by hand or tap with something
mildly heavy (1-3 lbs) should take it the rest of the way. If you can now
adjust length. If you want to take the bolt completely off just repeat
above steps for the other side. BE CAREFUL, if that bolt falls down into
the engine bay you are really in the ****. To put the bolt back on just
place the open end of the bolt over a mounting point and pinch it on with
your fingers, it should snap right on. (be damn sure to wear insulating
gloves through this) If you need help twisting any of the nuts on the bolt
you can use the small wrench in the OEM toolkit. (8mm I believe)
Adjusting length should be a snap once you brake it loose and get a good
look at it. Longer bolt = more aggressive shifting. Shorter bolt = less
aggressive shifting. Keep an eye on the arrows for reference. I like it
about one full "revolution" (that term will make sense once you get it out
mess with it) past "spec". You can tune it to your preferences. For quick
reference: break loose, adjust to spec, put back on, take one end off its
mounting point, then adjust the bolt one "revolution" at a time until you
find a setting you like..."


------------------
Best regards, Michael
'92 500E
'88 300TE
  #5  
Old 08-30-1999, 09:12 PM
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Join Date: May 1999
Location: Berkeley, CA
Posts: 199
what might be the problem if my 500E tranny does not immediately find reverse gear ( usually have to wait couple of seconds before it engages. if i press the accelerator before, the engine just spins the engages reverse with a sharp jerk)?
  #6  
Old 08-30-1999, 09:34 PM
EricH
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Anyone ever hear of swapping out the valve body in the Trani with one from a Porsche 928?

I know that people did this with the trani in the 560SEC and SEL with good results but don't know if its the same one or not.



[This message has been edited by EricH (edited 08-30-1999).]
  #7  
Old 08-30-1999, 10:50 PM
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Join Date: Mar 1999
Location: Suwanee, GA, USA
Posts: 4,712
There were a few factory mods where pieces of the tranny were updated with new parts. And in some rare cases the valve body had a small hole drilled in it. Your dealer will know more.//...

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  #8  
Old 09-01-1999, 01:09 AM
EricH
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I've been hearing a lot of info about these transmissions. And am getting more data on what might be wrong with mine.

AMG, Rennetech, etc make modified valve bodies that allow the tranis to always start with 1st, and some AMG cars got the p928 valve bodies which are not the same mod.

my *car* will not always engage 1st even if I have the shift lever in the 'B' position. Occasionally it will slip into 1st but its not a given that it will even from a stop. What might this symptom indicate?

I'll be taking it in to a A/T professional soon, since it seems more than just an adjustment. Unless one of you Star (pun intended) has a suggestion????

Thanks
Eric
  #9  
Old 09-01-1999, 02:30 AM
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Join Date: Mar 1999
Location: Atlanta, Georgia, USA
Posts: 1,342
Eric,
Judging by what you describe, there is something more than just "being out of spec" wrong with your tranny. That being the case visiting, a dealer, reputable independent, or german tranny specialist would be a good idea. That M119.974 engine is really a torquey SOB. Given many years and miles of aggressive driving it can surely be hard on a transmission. Especially if the previous owner did not follow MB maintenance intervals precisely.

Let us know how it turns out...Lee

  #10  
Old 09-15-1999, 08:24 PM
EricH
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Problem Solved!

Here is what it was....one of the wires to the kickdown switch had been pinched (by what I don't know) and thus the switch was not working properly. My car now will rev to 6200rpms in 1st before shifting and downshift properly. I can finally get all the car has off the line. So watch out bimmers, and yes, you too C36 and C43!!!!

Thanks to all that helped,
Eric



[This message has been edited by EricH (edited 09-15-1999).]

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