dmac5356

My '04 C320 4matic tranny has problems:

1. When I tried to replace the electrical connector pilot bushing the old one will not come out. It feels like the screw is just spinning. Either the screw is broken off in there, or the nut in the conductor plate is spinning. Ideas on how to get this out?

2. My tranny is jerking and clunking - possibly during some shifts, or maybe when the torque converter locks/unlocks. Initially it was only a problem when the transmission was "cold", and cleared up after a short drive. Now it's happening all the time. I did a complete flush/fill of the fluid, plus new filter. No metal in the pan. No improvement. So I just ordered a new conductor plate to see if that helps... but I need to get the connector pilot bushing out first (see #1 above).

Help is appreciated!

C240Keese

The point of replacing the electrical connector is because it was leaking. Is yours leaking ? if so you'd want to check behind the passenger foot area and check the TCM because that were the fluid is going. When it hits that your gonna be sorry I caught mines just in time.

When removing the old connector the screw doesn't come out it just loosens then make sure the tab on the outer ring is all the way down. Don't break it, then you should be able to pull it out when you do fluid will begin to come out quickly so have the other one ready to be pushed in. You may need to put a flat head in the connector and use a hammer lightly to make sure it goes all they way in or the tab will not turn. I did this before I went to work and the hardest part was getting it back in.

For the jerking did you check fluid level first you may need to get yourself a dipstick. Its a thread somewhere around here with how you can make one with a wire hanger or Search for one on eBay they're like $15

dmac5356

Thanks for the speedy reply!

Not leaking (yet!). Initially I wanted to replace the connector just to prevent a future leak, but now I need to remove it to be able to get the conductor plate out.

By looking at the new part I know the screw does not come all the way out. However, with the screw "loose" I am unable to pry the connector out without breaking something. The screw does not feel loose, and it won't tighten either. I think the nut insert in the conductor plate is spinning when I turn the screw, but still attached enough that I can't remove the connector.

Has anyone else had this situation? What if I put a needle nose vice grip on the screw head and pull out while I twist? Or will I have to bust it out when I replace the conductor plate?

I have an eBay tranny dipstick and have verified the fluid level.

My best guess is the speed sensor on the conductor plate is bad. I think it is locking up the torque converter at inappropriate times - ie: the input and output shafts are not at the same speed when it locks, so it jerks. The shifts themselves are smooth. Hopefully a new conductor plate will fix it!

C240Keese

Um its rare that it would be stripped unless you know if someone was already messing with that screw. When i was doing mines i had the wrong size socket. Hopefully you are using the wrong one as well.

dmac5356

7 mm IIRC?

C240Keese

I checked my old one and yup that's the right size. Yea I would say pulling and twisting with the pliers is a good bet.
Well that sucks hopefully you get this resolved

dmac5356

The previous owner of my car had the tranny fluid "changed" at a dealer about 10k miles ago. They put the pan bolts on crazy too tight. One torx head stripped when I tried to remove it, so I had to cut a slot in it and struggle for an hour to get it out. My theory is they might have replaced the connector at the same time and over tightened its bolt to the point where it dislodged the nut insert on the conductor plate. They must have done the 4 quart change, because the fluid was brown, not red. If all this is true, we should avoid dealers!

Dollos

Avoid dealers anyways boss....

dmac5356

One mechanic who works for a Twin Cities BMW dealer told me he earns $15/hr. They charge customers ~$100/hr? Crazy!

dmac5356

I replaced the conductor plate today. I had to break off the electrical connector from the old plate because someone had tightened the bolt so far that they spun the nut insert in the conductor plate. I tested the solenoids with a 9V battery. When looking down at the conductor plate with the electrical connector at the upper right:

- the solenoid at the upper left barely clicked
- the two on the lower right chattered, like on/off/on/off...
- the rest of them clicked as I would have expected

Does this sound right? Or do I have solenoid problems?

I put the solenoids into the new plate, installed the plate/valve body assembly back into the tranny, installed a new electrical connector sleeve, reconnected the wiring harness, put the pan on, refilled with proper fluid, and test drove. It still has exactly the same problems as before (described previously). Does anyone have an idea of what to do next before I throw crazy money at a shop?

Edit: I'm thinking the problem might be with the torque converter lockup solenoid (sometimes called TCC/PWM or Y3/6Y6), part number 1402770435... thoughts???

Dollos

Since you have done all the above already, u might as well change the tcc solenoid and put the tranny back . get someone with a c4 sdconnect to do the torque convertor adaption sequence and the gearbox adaptation sequence.

dmac5356

I replaced the TCC solenoid. I also looked over the transmission computer under the passenger floor - no fluid present, completely dry.

Still bumps hard each time the torque converter locks. Next step is a shop.

dmac5356

In an ongoing effort to stay clear of dealers (and other shops), I decided to order Sonnax PN 68942-23K TC Damper Valve, as Sonnax states it helps with harsh lockup - which is exactly what I have.

I also ordered Sonnax PN 68942-05K Overlap Control Valve Sleeve Kit, just as preventive maintenance.

I'll report back on success or failure.

Khan28

I have a similar problem. Had the tranny fluid changed and it got better for a while but returned. Then had the conductor plate changed out along with a new connector as it came in a kit but the same issues occurred. The error codes (on the mechanic's computer) present prior to the plate change were gone after the conductor plate was changed so I'm not sure where to go next. I get the problem mostly when slowing down from say 70KPH to 40KPH and gently getting back on the throttle. I feel a clunk and hear a physical clunk from the rear. Sometimes it will bang when shifting into the next gear if I'm driving at around 30KPH to 40KPH. Other times it's so damn smooth I can't feel it shift which is what I think it should be shifting like.

I'm wondering if there's some sort of coding only a tech with a computer can do. Anyway, I'll be looking into the TCC Damper Valve. Heck, I've already thrown $1300 at this damn tranny so what's a bit more? All I know is that when I buy another one of these cars I will buy the longest powertrain warranty money can buy.

dmac5356

I have about $600 into my transmission at this point, although $200 was preventive maintenance that I would have done anyway.

The Sonnax parts are only $85, and I will re-use my nearly new transmission fluid (drain into a clean container, and pass it through a fine-mesh filter funnel). If this doesn't work the only other thing I can think of is a fully rebuilt valve body ($$$).

dmac5356

Mine has gentle shifting followed a bit later by a clunk... the torque converter lockup. Yours may be different with a shifting problem.

dmac5356

The old valve was slightly stuck in the bore, I forced it out by spraying electrical contact cleaner through the openings under the TC solenoid.

The new valve fit fine, although the instructions were lacking. The kit includes a small c-clip, but the pictures do not show where it goes and the instructions don't mention where to put it! I elected to not install the clip at all.

Edit: This was a mistake, the clip needs to be installed, see below for details. The Sonnax instructions are awful!

I also installed their shift valve kit. The parts are the same as OEM, but they add an o-ring to make a better seal. I was not having shifting problems before, so no difference from this kit. Maybe it will prevent a future problem.

Khan28

So the TC damper valve and shift valve kit are 2 different parts? I do have the occasional shifting issue but say if I'm moving in slow traffic at a slow but constant speed the tranny holds the gear and as I slowly increase the speed of the car by pressing the throttle or slowing down the car by lifting off the throttle but not pressing the brake pedal I feel almost a physical movement in the drivetrain which does feel like TC lockup albeit a bit violent and you hear a clunk. I'm thinking maybe I should also look into new tranny mounts and if I do those I might as well do the engine mounts too. I'll speak to a mechanic about the above mentioned parts and see what I'm looking at in terms of cost. Digging into the tranny seems a bit more than what I want to do myself. The weird thing is when the tranny acts up it's always when I let off the gas or go to get back on the gas after slowing down but not stopping completely and not when I am on the gas. If I accelerate normally from a red light 1-2 there's the slightest jerk if it shifts before 3k RPM and the other shifts are buttery smooth.

dmac5356

Note: I emailed Sonnex and the clip was supposed to be installed on the innermost groove in the sleeve. I get to take things apart yet again to install it!

dmac5356

The Sonnex instructions are terrible. If you want to try installing the Sonnex TCC sleeve and valve:

- You MUST split the two valve body casting halves
- The sleeve must be inserted WITHOUT the circlip. You must push the sleeve all the way to the bottom of the bore
- You install the circlip through the passage to the side of the bore. I suspect this will be difficult as the clip fits extremely tight and there will be very little room to work

NONE of the above is in the instructions... which simply show the sleeve being slid in from the side.

I messed up the installation enough that i have ordered a rebuilt valve body.

dmac5356

The rebuilt valve body was worse! Hard shifts in multiple gears, harsh toque converter lock.

I properly installed a new Sonnex TCC sleeve kit into my original valve body and put that back in. It is better, but has a hard 2/3 shift. Note that it shifts fine if I use the manual function! I brought it to the dealer to get the tranny adaptations set, per various online and Indy recommendations. The dealer called and says the clutch packs are bad as indicated by K codes in the tranny controller. They quote $5,500 for a reman installed - which is way too much.

Also they said my engine ticking sound is due to scored cylinder/piston or carbon on a piston. How can either of these create ticking? I was thinking bad/loose rod bearing.

I bought this car because I read that the M112 engines and 722.6 transmissions are good. What a mistake! What should I do with this POS?

Khan28

Dang that's not good. I thought you were in the clear when you initially installed the Sonnax kit despite not installing the clip that it came with. I was thinking about talking to a good indy shop regarding the kit but have been questioning if this is the issue or should I get a whole new valve body. Hearing your story I will definitely NOT do that. I'm wondering if I have issues with the gears in the transmission or if it's a valve body issue. I just hate that at times it operates smoothly in any situation and acts up at times plus I'm not sure which kit to purchase as there are many for the 722.6 and a rep from Sonnax recommended the same kit you used when I emailed them. As for your issue with the motor scored cylinders can cause a ticking sound but it will be a heavier sound somewhat like a knocking that won't go away no matter the temperature of the motor or oil used. Get a shop to use a boroscope to verify that. You never know, the dealership could be trying to take you for a ride.

BTW according to the indy I went to initially to have the transmission fluid changed he said if the fluid is brown then that would indicate worn clutch packs. When you opened up your tranny what color was the fluid? I'm not sure what others think but based on the amount of problems the 722.6 and 722.9 transmissions are giving I think MB transmissions are a joke and sadly that's the only problem I have with this car but it is a big problem. Sad to know that the 4 speed auto in my previous car, a 2000 Nissan Maxima with 340,000kms when I got rid of it, shifted as smooth as smooth could be in any situation and all I ever did was a tranny fluid change at a crappy auto shop.

dmac5356

Tonight I responded to a Craigslist ad... guy has a Star tool and is recovering the cost by viewing codes and adjusting settings for people. He really didn't know much about the tool, so at first he just cleared codes - no improvement. He didn't realize that the transmission adaptations could be reset as a separate action, and at first refused to try. I talked him into it and... it works perfectly now!

My interpretation is my original problem of harsh torque converter lockup might have been fixed with the Sonnax kit plus reset adaptations. All the other things I did, like trying that rebuilt valve body, may have caused the adaptations to get even worse causing the problems to progress.

The Mercedes dealer simply read the adaptation values, which were way out of tolerance, and declared the transmission bad. They didn't reset anything. All I got was a $150 car wash from them!

So my next problem is the ticking engine. It sounds like a lifter, and one indy shop thought it is a lifter on the passenger side. So I replaced all the lifters on that side myself, with no improvement. However, one of the new lifters came apart before I installed it. It is just two halves that push into each other so I put it back together - but I might have replaced one bad lifter with another??

I have pulled the wires from each coil, one at a time, while the engine was running, with no change in the ticking. I think that eliminates the "carbon on a piston" theory from the dealer. Besides, inducing detonation at idle seems unlikely or impossible? Also, this seems to eliminate rod knock from either the small or big end - although I welcome other's ideas on that.

The oil and oil filter have had no indication of metal, and the oil consumption is not bad - which I think eliminates the dealer's idea of a scored piston and/or cylinder. I have a boroscope and may try peeking into cylinders just to see if anything is going on.

I do not recommend Feldmann Imports Mercedes in Bloomington, MN!

Khan28

If you don't mind me asking how much did you pay for the rebuilt valve body and where did you order it from? Perhaps I should just go that route since it should have new springs and clips in it. What exactly did the guy with the Star Tool do to reset the adaptations. I'm sure I can find someone with it here in the GTA since it's a huge highly populated area. Since the tranny in my car has new fluid (twice) plus a new conductor plate and connector and no fluid detected in the computer the valve body and adaptations has to be the last probable thing wrong with the tranny otherwise it's an internal failure with the gears or TC though there's no shudder that would indicate a bad TC. Also how much miles on your car? I only have 121,000 kms or around 75,000 miles.

Still run a boroscope through the spark plug holes to rule out scoring. Also if one of the cylinders has the intake valves slightly open you'll be able to see if there's carbon built up. Also, pull off the MAF sensor (might as well clean it whiles you have it off), the plastic elbow piece and check the breather tubes for carbon. If you have a mirror you can see inside the TB to see if there's a lot of black stuff in the intake manifold. When I just bought my car 2 years ago it had a rough idle at cold start along with a burbling sound from the exhaust. As soon as I cleaned out the MAF sensor, breather tube and TB it ran very smooth.

dmac5356

My car has 113,000 miles.

Does your car shift better when you try to control it manually? Mine did - which suggested the mechanicals were probably okay and the computer was messed up.

I don't remember the exact menu options he used in the Star tool, but it was pretty obvious. Something like transmission, adaptations, reset.

I got the valve body from RevMax. Cost was $299, plus $150 core charge and $60 shipping (yikes!). They have agreed to accept my return of the overhauled unit since it made things worse. I'd definitely have the adaptations reset before going this route.

Removing the valve body is not difficult, just messy - I have done it 5 times now! I bought a large black plastic pan (intended for mixing cement!) from Home Depot to catch most of the fluid. I kept everything very clean, and reused my new fluid (had changed fluid early in the program). I also passed the fluid through a fine screen funnel to be safe. Taking the valve body apart was easy - I did that inside that same black pan to prevent losing small parts. There are several small plastic ***** and steel ***** that need to go back into their proper holes. Diagrams showing where they go are easily found on Google. There are a couple small screens/filters that may fall out, and again are easily put back in their spots. Use my previous directions to install the "68942-23K TCC Damper Valve and Sleeve Kit" - it was easy once I figured out what to do. Note: chamfer the opening in the valve body to allow the o-rings to enter easily or they can tear. I also installed "6894205K Master Overlap Sleeve Kit" which was self explanatory and easy. I did not use any other Sonnax kits as they involve some machining. I don't know which of my many changes actually fixed the root cause, since I was unable to get the adaptations properly reset until tonight.