91 300D 2.5. Wont Go Over 2,000 rpms! - Page 3 - PeachParts Mercedes-Benz Forum

JamesDean · #31 09-03-2012, 05:45 PM

Quote:

Originally Posted by sixto

I doubt starting in second makes any difference to EDS. Load drives production of boost. RPM is a byproduct.

Sixto
87 300D

Can the transducers sense (in some way shape or form) that the object they are engaging has failed and no longer holds vacuum? Neither my EGR or flap devices hold vacuum anymore. Just curious.

I'm planning on performing the wastegate mod as posted by gsxr. The price is right and it definitely makes sense.

sixto · #32 09-03-2012, 06:11 PM

I doubt it. EDS knows something's wrong when a transducer command doesn't result in an expected change in the MAF signal.

Sixto
87 300D

JamesDean · #33 09-23-2012, 01:41 PM

OK so I worked on the transmission a bit this weekend.

I found that the governor was not fully seated or the snap ring had somehow released and let the governor pop out.

Now I am having difficulty fully compress the snap ring and push the governor inwards.

Seems like a three or four handed job and unfortunately humans only have two.

I need to use two to compress the snap ring fully, one to push the governor inwards and one to hold a light.

I also ordered a pair of these, they are for 50mm deep bores so I think that might do the trick. I found a set that would do 65mm deep but they would have to be shipped from Malaysia...

So my working theory is :

- Improperly installed governor was causing transmission to start out in second gear.
- Staring out in second gear caused delays in normal turbo boost timings
- timings caused EDS pressure sensor to not see boost when it was expected
- EDS throws code 14
- EDS kills boost.
- Car is slow as turd.
- Kickdown functions are inhibited by pressured changes due to governor installation problem.

JamesDean · #34 09-30-2012, 12:00 PM

An update:

The car is now driving normally, as normal as it was when I bought it.

Here is what happened:

When I originally installed the governor, I did not fully seat it. So once the output shaft spun the governor was forced out of its bore and up against the bore cover. This kept the governor engaged adequately so that it could still create pressure and shift the transmission.

The governor is now fully seated, the car HAS first gear and shifts normally. That above pictured tool:

Motion Pro 08-0279 Master Cylinder Snap Ring Plier : Amazon.com : Automotive

Worked nicely and was worth the cost.

Also the secondary pump has been disabled. It was removed and the two drive gears on it removed, then the pump was re-installed. I found a few posts on here indicating that if the secondary pump should seize it will cause the governor to shear the gear. I am not sure if that was the original cause of the governor's failure or it was just age. I didn't want to take the change anyway.

Here are the gears:

gsxr · #35 10-06-2012, 09:56 PM

Quote:

Originally Posted by pawoSD

The later cars all start out in second...both gas and diesel. It will only go to first if manually shifted there or if the pedal is mashed (kickdown switch).

This is incorrect. All W124 diesels start in 1st gear. Or rather, are supposed to start in 1st gear, when everything is working properly. Only certain models of gas 124's start in second, this varied by year/engine/model combination. There is no simple year cutoff where you can say "all cars after 19XX start in second". I'm with Sixto, the 2nd gear start is from the devil, lol.

BTW, JamesDean - glad you got the problem figured out! The car should be back to 12-second 0-60 times with full boost and proper tranny shifting.

JamesDean · #36 10-14-2012, 05:27 PM

Oh hay look we're back here.

Was running 0-60 times today and on the pull back up into the driveway.. No power. Yep governor poooped back outwards again. No damage to gears. Just not fully seating. So new plan is to completely cut the secondary pump.

The drive gears have already been removed. Now, we are removing the shaft and all that jazz. Ideally I want to just remove its carcass and put the proper plate on it.

I think I found the plate but the picture does not look like a plate. It looks like it has a hole in the middle of it.

Would the intermediate plate have to come off too? This is all really moot at this point as if gutting the existing secondary pump works and the governor seats fully all will be done and hopefully I will never update this thread again.