Early 99 Shifter slow to return to center

When cold it won’t return to center at all from right to center ( moving back left ). when cold it will slowly return to center from left to right ( moving back right) when warm it moves back to center both ways but still not as happily as it shoukd While I’m no mechanic I am fairly certain my issue is internal and not with the cables or the shifter. It did it with oem old shifter and it does it now with new shifter and new cables. So it’s fluid temp related. It gets better when warm. So I’m hoping I can flush out the old with an oil with a cleanser of some sort then put some new fluid in. It can’t hurt but not sure it will help either. Any ideas to what is going on internally with my trans? ** UPDATE ** See post 7. We are going to try to clean this detant spring / pin

My brother thinks it’s gummed at the shift linkage? Do these have grease there?

There isn't much in the way of external linkage on the 996 gearbox. Just two levers where the cables connect. If you've replaced the cables there isn't much more to be done. Perhaps a look to see if the cables are properly installed at the gearbox end, and that the bracket isn't bent at an odd angle or somesuch. Also was the Porsche shift alignment tool used when replacing stuff? That can make a significant difference in shift action. All that said, if it gets better as the car warms up I would definitely do an oil change to see if that makes a difference.

Thanks that's what I thought. Just the pin connectors on this one. Time to change the fluid. Any recomendations on a "flush fluid", warm it up then dump it? Or just drain and replace?

See post #7

The general consensus seems to be about 50/50 on the �flush�� Personally, I don�t think it would hurt anything, but you never know. I�d opt for doing it without the flush first, and see if it changes. Definitely get the trans up to full operating temp before draining. Be sure to use Porsche approved 75/90 gear oil (I used liqui-moly and it�s fine - a bit better than what I changed out).

He says it's this. Needs to be cleaned out. So maybe I'll just get new? Porsche 911 Carrera Gbox Second Gear Shift Detent Installation - 996 (1998-2005) - 997 (2005-2012) - Pelican Parts Technical Article

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Thanks, he wants to either clean out the Detent or get new, then of course new fluid. In terms of a flush, many are telling me to just warm up and change also.

The whole flush thing always seemed a bit too **** retentive to me. I went with Porsche brand gear oil. Lots of opinions on this though. The Porsche oil did improve cold shifting, but there is still some balkiness for the first few miles.

So I am betting your cables are old and fouled and have never been lubricated, or someone who didn't know any better used grease on the cables. They are just like the ones that run a power boat shifter, they use a gadget to force ATF through the cable housings on a boat.. Same with boat steering cables.. I would probably remove the cables from the car and take them to a boat shop... it can b messy..

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My cables are new factory. It has nothing to do with shifter and cables. It's internal in the trans. We will be cleaning out / replacing the return springs soon enough. I'll certainly updated everyone here and post a video on youtube since no one apparently has before. My mechanic has done this many times before, none with me so I'll be the first recording the process.

Ah,, good to know. My trans has 118K on it, the levers move like rifle bolts, be interesting to see the internals on this issue.

I have the same car as OP, and I've just finished diagnosing this exact same issue as we speak. Since my car turned out to be the worst case scenario, here are my findings to hopefully help others in the future: 1-Disconnected the shifter from the cables and it moves freely. 2-Disconnected the cables from the transmission and they move freely. 3-Flushed the transmission with OEM Porsche gear oil and no change (shifts nicely though) 4-Removed transmission to replace the spring for left/right motion since it's externally accessible from the top, no change. 5-With spring removed cycled the lever throughout its range and all the resistance is coming from there. Conclusion: Left/right lever shaft is binding within the transmission housing. I suspect this is caused by metal particles from a failing bearing. This would require at least a partial teardown to repair (maybe full). Since I'm already in process of a major engine service (IMS, Clutch, Variocam Actuator, Chain Guides, etc), I don't have the funds for a transmission rebuild on top of that. So after a quick brainstorm with my mechanic, we've decided to try shimming the new spring with various thicknesses of washers to raise the spring rate, and hopefully offset the resistance. I'm fully aware this is a bandaid fix, but it's worth a shot until I can handle a full rebuild. I will report back with the results once the car is back on the road. .....I have terrible luck with cars....

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If indeed there is a failed bearing you stand to damage more of the internal parts by continuing to run it. If you really want to do this, I would probably dump the gear oil and fill the trans with some light oil such as ATF or kerosene. Turn the trans so the selector shafts are submerged in the oil. Exercise the selector repeatedly in an attempt to flush out the contaminants. It might help to spin the input shaft while doing this in the hope that the fluid splashes around more. Then drain the fluid. Might be a good idea to do this repeatedly until all the removable debris in the trans is out and your flushing fluid drains clear. Do this at your own risk as it's possible that contaminants will move around and end up in other bearings.

There is no "bearing" on the shaft that controls the left/right shaft gates.. It's simply a steel shaft turning slowly in an aluminum bore...Likely cause is water/salt corrosion between the metals... Since the transmission would have to be disassembled to remove the shaft and polish the bore..... I think I would try a solution of 50% Acetone 50% ATF from the outside to see if it will penetrate the corrosion.. Acetone/ATF is one of the best penetrating oils known, better than PB Blaster..

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Good point. I forgot to mention that before filling with OEM gear oil, I did put a 50/50 mixture of generic gear oil with ATF and went for a short highway drive till warm, avoiding shifts as much as possible. That didn't help. Trust me, I recognize the risk. But, this is only temporary. I was referring to a pinion or gear bearing. I doubt corrosion in the bore since this is a summer only car, but I'll definitely try the acetone/ATF mixture anyway. I hadn't though of that. Do you think it would work it's way past the seal enough to actually make a difference though? OP, sorry about the hijack.

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The Seal not only keeps oil in but keeps water/corrosion out. The Seal is probably not sealing effectively to begin with.....but nothing can leak out because of the corrosion/tightness stops it.. I'm certain you could push some penetrating oil passed the Seal....and once the corrosion is dissolved the shaft will turn easy and may even weep a bit of oil ,but in lue of the alternatives which is to disassemble the trans and fix it, or to live with a binding shifter, I would do it. At worst you would have a weeping Seal that would need to be replaced at some point down the road.. Good luck !!

Is the spring in question, the one in this video, You Tube ? Man in a Garage accidently unscrewed the bolt holding this spring in place and had to fix it.

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Yup that's the spring I was dealing with, but not sure about OP. So here's my update: Penetrant on the inside shaft from the access hole did not work. Instead we went ahead with the shim, and new spring since it was slightly stiffer. The end result is good. I still feel some resistance, but the shifter does return to center enough that I don't need to worry about missing a shift. I feel this is as far as I should go with shims, otherwise it will take too much effort to shift to reverse. So there is my band-aid solution until I can rebuild the trans. I don't suggest it to anyone, but that's what I did.

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Did your "return to center" get better when the car got warm? Mine does. Isn't perfect like snap back but it does go back. If I were to go try it now ( hasn't moved in 2 weeks) it wouldn't move back at all. That's why we think its the assembly on the outside of the trans. It slowly warms up. Anywho, I just ordered all the parts, so we will be doing it in the next few weeks.

Yup, it was exactly as you describe. Once the transmission got nice and hot, it started to return to center, but never like it should. I strongly suggest you disconnect the cables from the transmission to confirm where your problem is before spending the money. It's very easy to do, and wont cost you anything.