Not shifting into park - shifter issue not transmission

[JeffSpicoli]

Hi All,
I searched and searched but came up empty. The transmission is fine on my 1993 euro 500E, no delay into reverse and shifts as normal.

The problem is that when I park and try to move the lever to P, it hangs up at R. It hits a hard stop, like a physical barrier. Now, if I drop the lever into 3 before trying to move it to P, it will go right in like normal.

Is there some kind of interlock that keeps it from accidentally going into P?

Thanks in advance.

tm

 

[gsxr]

The only interlocks are the steering & brake pedal interlocks, but I don't think either will cause what you describe.

Have the shift rod bushings (underneath the car) been replaced at some point? Wouldn't hurt to inspect both...

 

[JeffSpicoli]

They were replaced about 3 years ago when we got the car. We haven't been driving much in the last year because it needed a rear wheel bearing replaced. Now that is complete so I'm driving it more. Hopefully this is something that will loosen up with some miles.

 

[JeffSpicoli]

I saw the writeup on replacing the bushing. Is the connection between the transmission shift lever and the shifter in the car a cable, or a rod?

 

[gsxr]

I saw the writeup on replacing the bushing. Is the connection between the transmission shift lever and the shifter in the car a cable, or a rod?

It's a metal rod about 3/16" diameter between the shift lever (flat metal protrusion below the chassis) and transmission lever.

 

[nocfn]

The shift rod may have been loosed when installing the bushings and now the rod and components have shifted. That is the only connection betwix the transmission and the shifter. If it is off at all it will not shift properly. @gsxr, Never had it happen to me but could a disintegrated NSS be jamming the works?

 

[JeffSpicoli]

Update

I took a look at the bushings as much as i can tell they're intact. I had them replaced when we got the car 3 years ago, I can't imagine they're worn with as little as it's been used since.

The shifter lever will shift the car through the forward gears, up and down no problem. The transmission responds to all of them, you can feel the engagement from N. No hesitation no resistance.

It will go into and out of N perfectly.

From P it will shift into R and continue down with no issue. It engages R almost instantly.

But while running there is something stopping either the transmission or the lever from going from D to R.

I mentioned while running because if in any gear I turn the car off, the lever functions as normal (with key ON). This makes me think its something electronic/electrical.

Also, and I'll have to wait until the car cools down to test this again, when I first started it today and was maneuvering it out of the garage around my wifes car the shifter went from R to D with no resistance. It was only after I had run up the street on an errand that the shifting became finicky.

 

[JeffSpicoli]

Tested and confirmed today. When cold everything is normal. Once up to operating temp, the difficulty begins.

 

[emerydc8]

The park-neutral safety switch is piggybacked to the shift linkage at the transmission shaft. It is made mostly of plastic. Maybe it broke internally or the tab on the outside is jamming something.

 

[JeffSpicoli]

It really feels like something is jamming, the odd part is that the "jamming" doesn't occur at all when the vehicle is cold.

 

[gerryvz]

Does your car have the E/S slider switch on the gear position indicator plate? I'm wondering if there is something connected to that switch's vacuum box on the passenger side of the transmission.

The only other two things I could see being faulty would the neutral safety switch, which does go bad, or an obstruction of some sort (like a coin) that is down underneath the shift position indicator plate.

First, I would take a flashlight and shine it down the shift lever slot while carefully moving the lever through the gear positions. You want to see if there is anything down there impeding the lever from moving.

Secondly, I would drive the car up on ramps, and then get under it and visually inspect while the engine is running and the transmission is shifted through all of the positions, to see if there is anything physically binding or hanging up. The linkage is pretty straightforward, and the bushings just press in, so as long as things are properly pressed, and the linkage is attached and clipped, there is nothing to go wrong there.

My money is that you have a faulty neutral safety switch.

 

[JeffSpicoli]

Thank you for the tips.

There's no e/s switch in this car (euro model sent to Japan, imported back here from Japan).

I just started it up, first start today and it shifts through the gears (stationary) fine. Up, down through each gear with no stop/block/jam.

I'm going to take it out later but I have a feeling it will act up once it (presumably the tranny) is up to temperature.

 

[JeffSpicoli]

Is there anything that prevents accidentally shifting into reverse while driving? Is that a function of the NSS?

 

[gerryvz]

Is there anything that prevents accidentally shifting into reverse while driving? Is that a function of the NSS?

In 20+ years of being in the E500E community, I haven't heard of anyone who has actually tried to grenade their transmission like this.....but I suppose there's a first time for everything.

 

[gsxr]

Is there anything that prevents accidentally shifting into reverse while driving? Is that a function of the NSS?

Nope... no safety nannies related to the shifter.

 

[JeffSpicoli]

Ok, kicking the dead horse again here

There is some mechanism which prevents you from shifting into D from P without depressing the brake. My question is when the switch is activated, is the "blocker" in the shifter, or in the transmission somewhere?

 

[gsxr]

There is some mechanism which prevents you from shifting into D from P without depressing the brake. My question is when the switch is activated, is the "blocker" in the shifter, or in the transmission somewhere?

There should be nothing preventing a shift from D --> P related to the brake. The brake pedal interlock prevents the opposite, you can't shift out of Park without pressing the brake pedal.

However, there is a mechanism that prevents shifting into Park if the ignition key is not fully off / position zero.

Both mechanisms are located on the passenger side of the shift mechanism, and are connected to the brake / ignition lock via cables.

Both interlocks can be disabled by cutting the cable. (Disabling without cutting requires more work.)

 

[JeffSpicoli]

Sorry, yes thats what I meant. Brake has to be pressed to shift into gear. Ok, so those cables are that lockout.

Thank you!! I'm getting closer!

 

[gsxr]

I can't remember if I verified the annotation below is accurate, but I think it is:

 

[JeffSpicoli]

Looking at that picture, the adjustment point must be at the pedal end.

 

[gsxr]

Looking at that picture, the adjustment point must be at the pedal end.

AFAIK there is no adjustment...? You'll have to locate the other end and check it out.

 

[emerydc8]

Looking at that picture, the adjustment point must be at the pedal end.

Hi @JeffSpicoli,

Any updates on this? Mine is doing the same thing. I tried to spray some silicon lube down into where the ignition interlock cable connects to the lockout mechanism on right side of the gear shift assembly (center console), but the large wire loom on the right side obscures visibility and I don’t know if any lube actually reached it. If this doesn’t help, the next step will be to check the cable at the ignition switch end. I already replaced the shift bushings and neutral safety switch to no avail.

 

[JeffSpicoli]

Hi Jon,
No updates sadly. I have a couple projects going and no time. Haven't really had a chance to even try disconnecting that cable. When the car is cool, everything is fine. It only happens when warm (so far that I've noticed.) which makes me think something is expanding with heat.

tony

 

[emerydc8]

Thanks, Tony. My problem happens so infrequently that I can live with it, but I think it's related to some other shift issues because both started happening at the same time.