FRporscheman

All 4 944/968s we've owned have had this "feature", so I take it to be normal.

RajDatta

Arash has a good point. Don't expect to idle like a Toyota. They all vibrate a little here and there.
Raj

mattipuh

The Gearknob vibration itself is not annoying, it's more the jerky movement of car when running on low revs on constant speed, 20-40mph.

Other issue I have is that when accelerating faster (so that wheels spin) cars rear wheels start to "bounce" from time to time, it acts similarry as if there was a traction control or smth which would limit wheels spinning. Because 968's shouldn't have any traction control option available, I thought this was because of poor suspension condition, which couldn't handle the power during faster acceleration on dry roads, or smth related to poor transmission / powerdrain condition. Because of this, I have avoided revving the car harder or dry conditions, just not to break anything, before I get the car properly checked.

However, yesterday I took the car off, and we had snowy roads, and of course had to practice my rallying skills and slide the car abit because so nice road conditions. Sometimes the wheels started doing the same "bouncing", so it appears also on slippery conditions, in where the suspension or transmission shouldn't be struggling, because the power gotten into road is so little because of slippery and icy road.

My car dealer was telling to me when i bought the car that there would be a traction control in the car, but I think he was getting the same strange behaviour from car's rear axle. Can this be somehow related to the gear **** shake during idle speed, something loose in the transmission / powerdrain?

anyways I'll have to get the powerdrain & enginemounts checked. Just wanted to share the weird symptons of car, if anyone has or has had similar problems.

RajDatta

Do you have an LSD in your car? It could be possible that your LSD id whats giving you this "bounce". LSD's do go bad and this is one of the behaviors they exhibit.
Also, look for play in your CV joints.
Raj

BADBERRY68

Wow, I have had the same symptoms for 2 years, jerking at low revs, especially in second gear. If I am moving along smoothly in a lower gear and hit a bump, it starts the jerking. Driving me Fing nuts. Trans mounts are fine, interested in the CV joint idea though. Anyone else?

mattipuh

At least option codes does not imply LSD, don't know if there's any additions done afterwards. Don't believe there would be, because sometimes car clearly spins only another wheel - no LSD. CV joints could then be one point to check. is it easy job to see if there's something wrong in there?

notthd

Read this eairler and thought I'd jump in. My 968 and previous 951 had the same shifter vibration and it was caused by a worn out shifter rod and transmission push rod. I am refering to the stem that is welded to the upright portion of the shifter that the push rod that goes to the transmission attaches to by snap ring. On both mine after time, the use of the shifter makes this pin no longer the same diameter across it, the ends become smaller than the middle allowing the push rod to the trans (sorry I do not know the official name) to vibrate side to side on the mounting pin. Also the push rod hole becomes beveled out and is a larger diameter on the ends than the original measurement adding to the shifter play. Grab the push rod keeping the shifter still and upright and see how much play there is by rotating the push rod back and forth. If it can be turned by more than a few degrees each direction this is adding to your vibrations. I have fixed this three different ways.

One way was to add delron washers to each side of push rod pin and forced the snap ring on. It takes up the slack by compressing the push rod onto the shifter pin.

Another way was I cut the pin off the upright part of the shifter and drill and tap a hole where it was and then used a sholder bolt to attach the push rod with lock tite. Worked very well.

The last is to replace the push rod that attaches to the transmission with one that is not beveled on the inside. Usually most of the play comes from the push rod. I can get some pics if you like-

Hope you all had a great Holiday- Mike

RajDatta

Mike, some pics would be a big help.
Thanks for sharing your insite.
Raj

notthd

Read this closer and had an idea- my 951 had a bounce problem like the motor would cut out for a split second causing a bounce or partial buck under acceleration. Looked at fuel, spark, CVs and it turned out that the set screw for the rotor had come loose causing the timing to retard slightly under load. Because it was not all the way out it still ran fine most of the time- someting easy to check..... I'll keep thinking and try too shoot some shift rod pics- Mike

mattipuh

Looked at fuel, spark, CVs and it turned out that the set screw for the rotor had come loose causing the timing to retard slightly under load. Because it was not all the way out it still ran fine most of the time- someting easy to check..... I'll keep thinking and try too shoot some shift rod pics- Mike

Thanks for the great update Mike. What set screw for the rotor you mean, engine timing? Mine sounds sometimes as it had a electrical traction control, as it would keep cutting the ignition while wheelspin.

Have to check those shifter rod and transmission push rods! Are they easy to fix, or does it require transmission removal?


p.s. My mechanic checked the CV play, and they were ok. I have also some problems getting the 1st and 2nd gear in, especially when the engine is cold, and after warmup still some problems with faster shifts to 2nd. Mechanic thought it might be smth with the worn clutch. Maybe trying that path, replacing first the clutch, and if it does not help, then maybe checking the syncros of those gears.

notthd

The set screw I am refering to is on the ingnition rotor on the distributor. Remove the cap and make sure it is solid on the shaft.

On my cars I had trouble getting into reverse and second when the shifter push rod wore out. After I fixed it these problems went away- I will shoot you some pictures this weekend. I have one not in a car I bought as a back up.

Easy test- with the shifter straight up can you rotate it in either direction? If it tilts and rotates its the rod. By this I mean can you make the shift pattern on the top of the shifter rotate or point towards the streering wheel and the glove box?

Hope this makes sense...Mike

Matt- just realized you are in Finland, I might be getting a job in Pori, I work For AREVA. If I come over I'll be in the market for a new P-car...

mattipuh

Ok, i'll have to check the ignition rotor too. I ordered some Bushes for shifter, to check and replace the shifter rod mountings. If it doesn't help, get the car up and check the shifter and transmission rod movement, if there's any slack.

The shifter stick feels quite wobbly - there's certainly quite much play in the shifter, so wouldn't be no surprise if the bushes would have worn out.
the shifting problem seems funny to me: sometimes the shifting is easy, and sometimes it requires more force to 1st and second gear. From this point it shouldn't be a clutch or cylinders, because shifting easiness varies so much.

BTW, is it normal that when accelerating (even lightly), and then releasing the accelerator pedal, the shifter seems to move. car does not do any jerky movements, but the shifter does. it is easy to notice when you grab the shifter, you'll feel some movement going on there.


You're possibly moving to Finland? That's nice to hear! We have active Porsche-club here, 1000+ members and good activities especially during summer time.

mattipuh

Replacing MAF to new one actually smoothened the motor in constant speed greatly, no judder or shakenes in constant speed of 0-40mph. Got also more power to +4000rpm, now car actually feels it could have that 220-240hp under hood, and seems that fuel consumption has also improved. great repair!