what is the little white box(under a black cover) that has vacuum lines going to it, that sits on top of the valve covers. The reason i'm asking is because i think it is leaking, and whenever i mess with it my tranny goes into gear smooth for a couple times, then goes back to being a harsh shift into gear. Also, how many lines are supposed to run to this thing? and as best as you can, can you describe where each line is supposed to go on that connector peice? what exactly does this box control, i know it is something throttle/tranny related, but i dont know what.
thanks
R

i made a mistake in my original post, there is 3 lines running to the box. I did a little experiment tonight as well, i unplugged the connector and blocked all the lines off with golf tees. What i found out is the first time i shift into drive it's rough, but then if i do it immediately after it's smooth as silk. And the longer i go(e.g. one block) without shifting into and out of drive again the harsher it gets. This has got to be somethign vacuum controlled as it was harsh as hell all the time previously. thanks
R

R,
You've discovered the switch over valve that is supposed to contorol your EGR valve. They are prone to leaking and the control "fingers" inside wear down throwing it out if wack. It causes your transmission to shift harshly because the vacuum leak is causing the modulator on the transmission to get the wrong signal. You can get good shift control by blocking off the vacuum supply to the valve and checking the adjustment of the control valve on the IP. Here is a link to a good article on making the proper adjustment. http://www.mbz.org/articles/trans/diesel.html If you block of the valve but follow the rest you'll be happy

Bob D.

thanks for the reply h20diesel, however i think you misunderstood my problem, or, i am misunderstand what you are saying. Let me try to clear up what my exact problem is, and then i will re-read your post several times. Once the car is in gear my car shifts perfect(e.g 1st to 2nd to 3rd to 4th etc)HOWEVER, it is GOING INTO gear hard. IN other words, when i shift the selector from Park to drive it engages quite roughly/jerkily. Same with going from park/neutral to reverse. hope this clears up any confusion, and once again thanks for spending your time to reply
Ryan

oh also, there is quite a bit of delay going into gear(park to drive) as well. I'd say about 3 seconds(mississipies). After i go in and out of drive once it engages smoothly and quickly-until i drive any more then about 50ft. thanks!
R

I was looking further down and saw stevebfl's post to some one regarding this. BB's in vacuum tube? BBs in vacuum Tube. Steve is a pro, take his word as gospel.

Bob D.

Rayn,

I'm still not sure I understand exactly what your discribing, but for optimum trans health I suggest you do a tranny drain and filter service incl. torque converter. Mobil 1 is worth the extra money (and I am very cheap). Then follow Dan P's article. I've done this and I now have two nicely shifting SD's

Bob D.

P.S. You do check your fluid fully hot idling in park and keep it exactly between the lines don't you.

thanks for the reply again H20, and i'll try to describe my problems again, the reason you probably dont' understand is this is not a very common problem at all(or so i've been told). When i move the shifter from Park or Neutral Into drive, there is a fairly loud clunk, and the car jerks quite a bit. This is in great contrast to the smooth motion it used to have. Remember, this is not shifting out of 1st gear into second etc, it is only when putting the car IN GEAR. As in moving the selector to drive after it's been parked. If, after i have put the car in gear once(and it does is harsh thingy) if i immediately put it in N BEFORE DRIVING THE CAR ANY DISTANCE and then back into Drive, it goes in smoothly like it should. This problem may or may not be related to vacuum but if it's not there are a ton of coincidences going on. By the way, this problem started after I had the valve cover gaskets done. Thanks again
Ryan