help!!!!me english is not very well but i need help from all of you.
i have 95 300sel with 722.508 gearbox and no 5gear, no kickdown, no downshift.
when I start drive the car gears shifting very fast in 40mph iam going on 4gear.
i rebuild the gearbox, change kickdown solenoid, change gear selector, throttle body wires change as well, presure cable is not broken.
help whats the problem with this gearbox?? I searching about this gearbox and found more peoples with this problem, but no answer for this question!! please help!!
Yes. Before rebuild gearbox no 5 gear. I rebuild it becouse other gears shifting not well and think servise fix and 5 gear but no. They say we chech everythink in gearbox its maybe problem in a car... and i dont now what to do... i change throttle body wirings selector, hgs , ant nothing.. no downshift no kickdown no 5 gear.
How are you thinking about maf sensor or its can be important? Or abs sensor? But i have and cruise control and speed on dashboard. No check engine light. No asr.
A 95 S320 should have a base module which incorporates the function of the OVP relay. It will be in the black box in the engine compartment with the other modules. It should have 3 fuses on top.
So, i'm short the shifter switch wires but nothing, but when i driving in D or short wires , and drive about 100km/h and release the accelerator, it feels like gearbox going in neutral. Then i release wires or turn knob to 4 is going i 4th gear, but when i turn again in D its going like neutral.
I have a similar condition right now. 1st to 4th work fine in 4, in D it slips out of 5th into neutral. Shift over to 4 and it goes back to 4th.
Mine started right after I did two things back to back - 1) changed the fluid, and 2) changed the shifter bushings, which were in really bad shape. So I'm not sure which induced the problem. I started with the hypothesis that the new shifter bushings caused some sort of alignment issue with the 4/5 switch and decided to replace that, only 17 bucks. I am right now trying to figure out how to remove the PRND plate around the shifter to get access to the 4/5 switch. It feels like it's welded on.
You description sounds like everything is working, and you may have worn frictions in the tail-cone of the transmission, but their is a module in the engine bay responsible for the 5th gear, and I had someone have this problem continue after a full rebuild of the transmission, and found the relay contacts corroded. Here is the thread:
Also i read in ignas forum, about remove hgs and try to drive car, it will be shift 5th gear instead 4th. So i try it, remove the hgs control module, but no nothing happens, so i thinking maybe somethere wires going in hgs module is bad? How can i check it or its can't be a reason of 5th gear engage?
I have 170000 miles, and wich relay it can be, where can i found it?. And little more about me 5th gear, before i give car to service, i driving without downtshift and 5th gear, but one day for a week maybe, appeared downahift kickdown and 5th gear i dont now what happens but car goint in 5th gear all time, but after rebuild gearbox im again dont have 5th gear. So its can be i thing just electrical problem... but how too find it? If that can be relay so where it is or i dont no...
P.S my coolant sensor is bad.
I thing maybe check speed sensor but i dont how my speed on dashboard is good.
I read more forums about my problem, and find information about bad head gasket which caused it to run lean and had low vacuum (like 12hg). What you thinking about it? Can this be a reason of 5th gear?
Make sure your vacuum lines are good. Under the intake is node of vacuum lines, and rubber wye deteriorates to starve vacuum to other parts, but not enough to stumble the engine, so you may not really see it..
Now, if the vacuum modulator is leaking oil at the nipple-The modulator has a leak, and must be replaced, and that has the possibility to cause all kinds of problems. It must be dry.
One can externally drive the vacuum modulator from a vacuum test-tool(gun) while the car is being driven using a long piece of vacuum line.
In w129 forum one men have same problem like my. Soo hi change the ezl ignition module and then can go good but in my w140 s320 95" no ignition module... what i have instead this module? Can anyone help me?
You have many moving targets, but what I would do is power the 5th gear solenoid from a external source once you are in a SUSTAINED Speed of 70Kh or so or higher, and based on the results the vehicle will be in 5th gear or not in 5th gear. If it works in 5th gear, then the problem is in the module that permits/controls the ability to shift to 5th. Consequently, no 5th then the problem is in the transmission with the 5th gear section, yet I currently have my own car in this state too, but for the moment I am not driving it because I have a bigger problem of these:
I will rebuild this transmission myself later as those springs are right behind the oil pump at the front of the transmission, and I need to remove the transmission from the car.
You problem may be as valve body deep, but it is hard to tell.. Here is a picture of the valve body showing a picture of 5th gear solenoid-Follow the black cable to the right. The cable attaches with Philips-Screw. Maybe the screw is loose, or the solenoid not actuate?
My tranny before rebuild, was like yours in photo. But before rebuild 5th gear works fine, just now its after 4th gear when going about 80km/h or more its going to neutral...
I try to do like you say, but who or where connect wires or what to try get 5th gear.
I now on tranny back is the solenoid so maybe this one i need to short?
It is not a short!!! It is about opening the circuit, and powering the circuit(one-wire to the solenoid) separately at 70Kmh.
You know really need to make sure the ground strap is connected from the transmission to a clean point on the chassis.
I could NOT find my service manual to the 722.5, so I do not know the color code of the external wiring harness driving the single white wire driving the solenoid. You need to comb through the diagrams to find that single wire coming from the back of the transmission .. From master PDF(post 26 of the link below) document-page 58- the black wire coming from back of the transmission. See the valve block. It is the control valve... Find that wire near the Kick Down Switch near the throttle pedal...
I want to ask one more question about circuit...
So i need to find on tranny back wire which going from the 5th gear solenoid, and with other wire straight connect to kickdown switch under gas pedal?
According to the diagram yes.... The kick-down solenoid in the transmission is isolated, and it has two wires going to it, so a total of three wires leave the back of the transmission.
Martin
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