300D Turbo Diesel refuses to shift past 2nd Gear - Page 2 - PeachParts Mercedes-Benz Forum

ggarvis · #16 08-06-2007, 11:13 PM

As I try to track down the leaks in the vacuum system how could I go about bypassing the locking system with out messing with other systems? Was told locks do not work and I tried them and nothing happens, so big time leak. Putting in a pick of the lines going into the firewall. Would I just plug the the yellow and the yellow green along with the black?

300D Turbo Diesel refuses to shift past 2nd Gear-84-300d-vacuum-system0007.jpg

hofler · #17 08-06-2007, 11:42 PM

Ggarvis,
Sounds like you are making good headway, I hope I will do the same as soon as I can get my supply line replaced and set about working down the vac lines to each system. Keep us all posted on your progress as I would hope to learn from what you discover.

Just a thought about the brake booster. what is the pedal supposed to feel like? I am not sure if it is the age of this car or if the brake pedal actually feels a little hard. I put my vac hand pump on there and after a great deal of pumping was able to get it to register that it was holding vac. I was thinking that if the booster was not holding vac then it would not matter what was connected to the nippples on that supply line. Is my logic correct? or am I over thinking this.

R

ggarvis · #18 08-07-2007, 07:59 PM

All, found another leak on the line from teh transmission vacuum valves to the ERG valve. At the end of the red handle the connector had rotted away and would hold no vacuum. Then at the yellow handle this had been disconected and capped off from the ERG valve. In testing the ERG valve it held vacuum and moved back and forth when a vacuum was applyed. Hook it back up. Have not tried to run it yet to see if there are any differences yet. See pic.

300D Turbo Diesel refuses to shift past 2nd Gear-84-300d-vac0002.jpg

hofler · #19 08-07-2007, 11:29 PM

Sorry to say I have not had a good chunk of time to dedicate to my hunt, ggarvis you just rock on!! Ok where is this erg valve as I am sure I want to check mine. So far all I have discovered is thatwhile everything had been connected to one nipple on the main vac line the lines that went through the fire wall held no vac at all. I know that it consists of ac, locks and such but what else goes through the fire wall. I noticed two brown lines that seemed to run in that direction one comming off the bundle connected to the vac supply line and another "return" (?) that seemed to be connected to the engine cut off valve. Yes? at least that is what I can remember... I gotta take pictures :-(
R

ggarvis · #20 08-08-2007, 08:44 PM

Hofler,
The EGR valve is below and infront of the air filter. There are some vacuum diagrams found on phantoms page. As I check out other post it seems a lot of people are disconecting the EGR all together. Brian Carlton seems to have a system to do this but must be sure of what modle you have. Brian if you read this what I have is the 84 300D Turbo diesel. Am I correct in that the ERG will only rob power on this model and can be bypassed alltogether by pulling the white line from the y going into the second y that goes to the tran and other to the green surge damper, then pluging it. Then taking the black line, from the 3/2 valves going to the y which vents to the passenger carpartment, remove it and plug the y. When the 3/2 opens and closes would there not be a slight reduction in the vacume going to the tran due the the additional venting?
Was able to get the motor to stop on it's own when I turn the key off by plugging the yellow line and the yellow/black line which go into the firewall. The Yellow line would not hold any vacuum at all.
Hofler you might want to read the thread by tankdriver "New member- (with transmission problem) and then another by Samuel M. Ross "It's CRITICAL... how you set your transmission's vacuum system on your diesel MBZ...

Dieseldoofus · #21 08-09-2007, 01:16 AM

I have an '83 300SD with the same motor, and disabling the EGR and associated vacuum lines GREATLY improved the transmission function. Remove the vacuum lines going to the black box on the valve cover and plug the holes wherever they terminate. (2 on the driver's side, 1 on the passenger's side) That's it. If you really feel like spruceing things up, take the cover off the black box (one blade machine screw) and remove the valve assembly (one allen screw). This should eliminate many potential leaks in the vacuum system. My car went from slam-shifts to butter.

ggarvis · #22 08-09-2007, 08:08 PM

Went fishing today and had a good catch.

300D Turbo Diesel refuses to shift past 2nd Gear-fishing-trip-0809070012.jpg

Before going fishing though I put the car away in the garage and fumagated the car. Had a problem of brown widow spiders having set up home under and in the engin compartment at the previous owners place. It started and turned off ok with only 3 min running time. Yester day I had disconected the yellow and the yellow-black line to the locking system to isolate that portion. Went to open the trunk for the fumagation and it was locked, the first time this ever happened since I bought it. Also the fuel door was locked for the first time. What do I need to do to disable the fuel door lock, can't open it no? Trunk opens with key. Will try isolating the EGR system and black box tomorrow and see what happens. The big fish was a 67 pound amber jack, the other a King fish 3', and in the amber jacks mouth a 3 pound vermilian snapper. Pulled up some sharks but through them back. Can not seem to access the i-spell check, I really need it.

hofler · #23 08-11-2007, 01:01 AM

Ggarvis,
I just noticed you are in Florida, Where bouts? Im in new Orleans, great catch. I hope to dive in hard core on my vacuum project on my 300D this weekend. I just gotta beat the heat. Hopefully I'll have good things toreport by Sunday evening.
Cheers!!
R

ggarvis · #24 08-11-2007, 06:38 AM

I live in Sebastian FL just north of Vero Beach on the east coast. Got my parts in from Diesel giant and will start on those items soon. But just found out need to replace the front break calipers and rotors. Check out the thread by Brian Carlton called "EGR blocking plate kit". They say removing all connections and even the EGR improves shifting.

hofler · #25 08-11-2007, 12:42 PM

Yes I pulled all those hoses and plugged thier respective spots in the splitters. Still no improvement.

I had been looking at my kickdown realy underneath the accelerator pedal. I tried it with the wires pulled off of it to see if that would improve things but no dice. So I also took a volt meter to the kickdown relay and believe I may have found soemthing. The kickdown realy gives a reading of an "open" circut, that is, it does not pass voltage when it is not depressed, reading zero on the volt meter, that is what I would expect. Then I put the volt meter on the two leads tht I disconnected from the kickdown relay and that gave me a reading of 100%, that is, a "closed" circut. Now I would have thought that it should have read "open" So what I suspect is that ther must be a short in the wires running between the kickdown relay leads and the where ever they terminate. Or do I have this completely backwards?

Yes I had it backwards

From
11:22 PM klataklatacoupe
"take an ohm meter and set it to measure ohms. put the leads on the two connections going to that button. if the ohm meter zero's out that means there's continuity between the 2 wires and they're shorted together somewhere. if that is the case follow the wires to where the enter the trans. "

I' keep you posted
R

Dieseldoofus · #26 08-11-2007, 08:19 PM

That's probably it. A short anywhere between the switch and where it goes to would look like a closed switch to the transmission.

hofler · #27 08-13-2007, 11:09 PM

OK, I got my new Vac supply line installed and now have the trans vac seperated from the rest of the vac lines that passs through the firewall. Now I definately have good vac going to the VCV 10 Hg. I read no leaks when checking all the lines from with in the engine compartment. I have also eliminated all the EGR connections. I still only get to second gear and no further. I have not disconnected my vac line at the modulator to see if it is clogged and not passing vac to the tranny. That will have to wait for another day.
As far as the vac lines going through the fire wall, the door locks do not leak, the green with the yellow trace does not leak, but the brown does. It will not hold any vac at all. When this is disconnected and a golf tee put in its place on the three way, I get good function from the door locks, albeit slow, but predictable. I have not checked what I get from heating and AC. I have also noticed that the engine will not shut off at all without doing so manually under the hood. So I gotta know just what does the brown vac line connect to once it passes through the fire wall?
And also any other sugestions as to what I can do next with my tranny to get past second gear?
Thanks for ny help anybody.
R

#28 08-13-2007, 11:13 PM

Quote:

Originally Posted by hofler

I gotta know just what does the brown vac line connect to once it passes through the fire wall?

The brown line goes to a vacuum valve that's built into the ignition switch. The valve opens when the key is "off" activating the fuel shut off.

hofler · #29 08-13-2007, 11:32 PM

DO you know if this is a pain in the a## to fix?

will_sanderson · #30 10-15-2007, 03:35 AM

It seems that you and I have the exact same problem at the same time! Amazing , thanks for all the posts it has helped a lot, I now have second gear all the time and sometimes third! (when I started I had first and sometimes a slippy second). I can hear a leak inside when I release the accelerator so I will look around and see if I can find.

I just picked this car up yesterday and am truly amazed at the ludicrousness of what the vacuum system looked like when I got it. I wish I had taken a photo but lets just say that 80% was disconnected and then 30% of that was reconnected wrong and there was a lot of electrical tape involved.