964 Weak Points

[si Banker]

I purchased a 964 with about 35,000 miles in November of 2012 and now has 45,000.
Since I purchased the car I have lowered it, replace tires, new brake pads and rotors and add a Wrong chip and cat by-pass. The car runs great; in my opinion it is the best of old and new and it is still air cooled.

Monday I had the shift linkage fail, this is fairly common and was fixed quickly but the car had to be haled to the shop. My questione is, "what are other weak points or things that could be replaced or changed before there is a problem. Is there any problems with the fly wheel set up or the twin distributers.

Any help would be appreciated. My last car was a 1987 Carrera which I owned for 11 years when it was totaled. I would have kept it much longer but..............................

[crg53]

As you mentioned, the distributor belt needs attention once in a while. If yours has never been changed, you should get it done and also make sure you have the "vent kit" installed.

[Vandit]

Weak point is usually the driver, mostly when you're trying to hustle the car around bends, lol.

Carry a spare DME relay.

At idle, measured at the battery, make sure your alternator is charging between upper 13s or lower 14 volts. If lower, your alternator may be getting weak.

Check your motor mounts for sagging.

The engine carrier bracket is weak and can break from hard use or stress from upgraded motor mounts.

The front control arm bushings are rubber and can fail w/ age/miles. Same goes for the bushings on the rear inboard spring plate. They can cause less-than-ideal driving dynamics.

The HVAC is problematic due to age. The blower wheels can make noise and eventually seize up. They're not easy to access or cheap to replace. Evaporator leaks can be a source of refrigerant leaks.

Are you the guy that goes to Cars & Coffee in Plano every month?

[Esel Mann]

For some reason the plastics don't seem to be holding up too well. For example the left/center/right rear reflectors have extensive spider-web cracking big time, on the console plastics the retainers like to break. And the price to replace? All I can say is wear a diaper before you begin to shop for those.

Electronics can be pesky as well. I just sent in my CCU. Diagnosis: more cracks in the solder joints than crack in crack pipes.

Gauges, they seem to not hold up in terms of the faces. On my speedo face the black background was cracking so that the backlight would shine through and it looked like looking up at the stars. On the oil/fuel gauge the face is peeling on the idiot lights.

For the above, true, nothing in the list would leave you down and out or stranded. However because of the not insignificant cost for the above, it is certainly worth: (a) keeping an eye out for good deals on NEW replacement parts. and (b) saving for a fund to permit strategic purchases.

[RSTarga]

clutch master and slave cylinders start to fail too. Brake lines. All of the above as mentioned. Nothing big, but the parts and some of the labor to fix can get expensive, eg A/C evaporator. They have to remove the fuel tank and fuse box to replace.
Motors are very durable. Use good oil and change often, not the 15k the factory recommends. I do 5k on Mobil 1 15-50.
Check your mirrors to make sure glass isn't on the verge of falling off. Window switches are common wear items.

[creaturecat]

Rust can and will creep into the front and back window seals, given half a chance.
It will leak/weep. if not now, later.

[BigMike62]

All good points but it depends on how the car was maintained and stored over the years.

Valve cover, cam chain cover, and oil pressure sending unit cover are the main sources of leaks. Also, the hose that runs from the oil filter to the thermostat seem to start leaking at the crimp more than any other oil line.

I recently went through a fairly detailed "oil seal" but replaced a LOT of "while you're in there" parts as well. When a car gets to be 20+ years old, things deteriorate over time.

[si Banker]

Thanks for the feed back. I will get the distributer up date kit. The engine is dry as a bone and as it has spent it's entire life here in Texas I am not worried about rust.

What about the dual mass fly wheels?

It's really funny the car does not need anything; just drive it!!!!!!!!!! Which I am doing, 8,500 miles in 9 months. Great Car

[Geneman]

hello si,
its frank from philly. i have been emailing you and trying to get in touch regarding the g50 +lsd that came out of your donkey-wrecked 87. we agreed upon the sale a long time ago.. and i have already paid you considerable funds. can you please pm me, email me : rauscher@wistar.org or call me on cell (you have my numbers). so we can complete this deal. i know you have been injured per our last correspondence, but apparently you can still post on pelican!!..which is a good sign.

thanks frank

[Spenny_b]

re your gear linkage failure - I just ordered a "Goldenrod" from Mark @ F D Motorsports...not sure which part of yours failed but may be worth looking into this as a sensible upgrade.

The dual-mass flywheels were a known weak point, can't remember whether they were ever a point of dealer recalls, but do know that Porsche switched suppliers.

The A/C was shot on my 964T when I bought it as well - it made for a good Easter holiday project. As mentioned above, it is a lengthy job, lots of stuff has to be removed, most of it straightfroward but some of it fiddly. There's a good online DIY for it though, which I found invaluable; take loads of photos as you go. In my case, a couple of steppers were knackered, the CCU was toast (even the eBay one I bought to try and salvage one good from 2 bad ones, was also dead but in a different way) and the evaporator was filthy/wrecked....I basically replaced everything apart from the pump!

The clock faces are easily fixed; in the UK we've got a guy in north London that can turn it around in a or so (in fact, he fixed my gauge in a few hours while I went into a business meeting); it was an ink problem with the original faces that causes delamination (apparently). I believe folk like Hollywood Gauges do the same in the US.

[si Banker]

I had wanted to power wash the transmission before I sent it out. I was also having trouble getting a good rate for freight from Fort Worth, Texas to Philli. Pa. I was able to get it shipped for $186.

It went out today you will have it monday

[rbogh901]

Originally Posted by Spenny_b

The A/C was shot on my 964T when I bought it as well - it made for a good Easter holiday project. As mentioned above, it is a lengthy job, lots of stuff has to be removed, most of it straightfroward but some of it fiddly. There's a good online DIY for it though, which I found invaluable; take loads of photos as you go. In my case, a couple of steppers were knackered, the CCU was toast (even the eBay one I bought to try and salvage one good from 2 bad ones, was also dead but in a different way) and the evaporator was filthy/wrecked....I basically replaced everything apart from the pump!

I've read Spenny's posts. He is a wizard.

Yep, HVAC is a common complaint although when functional it is far superior to pre-964 heating and A/C.

What DIY link did you use? How did you finally source your bits? Tell us you didn't have to go to the dealer...

[Vandit]

Here's a DIY for the evaporator.
993 A/C Evaporator replace DIY

Regarding the DM flywheel, I thought that was an issue w/ the earlier 964s. I wouldn't think a late model RSA 964 would have an affected unit.

[Spenny_b]

Originally Posted by rbogh901

I've read Spenny's posts. He is a wizard.

Yep, HVAC is a common complaint although when functional it is far superior to pre-964 heating and A/C.

What DIY link did you use? How did you finally source your bits? Tell us you didn't have to go to the dealer...

Awww shucks....thanks but wizard I'm not, annoying perfectionist? Definitely...and pretty relentless? Yes, perhaps...mixed with a healthy dose of nerd-ism, lol!

I've never experienced pre-964 AC, but I'd say that a working 964 setup is probably 80% of what a fresh modern production car offers....but perfectly good enough

The link in Vandits post is the one I used - some jobs are two-handed the first time you do it, really just to save any risk of scratching paint when fighting the HVAC unit - its a bit of a bear. I can't remember which bit it was, but I had something that I reinstalled 180degs out....meaning the whole lot had to come back out again. I didn't swear too much...cloud of blue-air just lingered over my house for a few days, haha.

Re DMF's, I think you're right Vandit, the problem probably was rectified later on in the 964's life....I know the 964RS had a single mass FW, did the RS America not have that too?

ETA - it was one of the servo arms that actuates one of the airflow redirection flaps in the HVAC.

[Spenny_b]

Originally Posted by RSTarga

clutch master and slave cylinders start to fail too.

Forgot to add to my earlier post, that I also had this before I pulled the engine; I had a lazy pedal return. From my limited research it's one of 4 items, either of the cylinders as RSTarga says, or the hose between the rigid line and the slave cylinder, or I believe could also be the pedal linkage - again I think there was a bulletin to fix it. I'm replacing the slave cylinder and the flexi hose - fingers crossed that solves it for me, if not then its pedal box disassembly time.

[si Banker]

What is it? Is there a fix for the fly wheels. I must say that the ac in my 964 is light years ahead of my 1987 and d I had spent a ton of money on it's ac system










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[Spenny_b]

Originally Posted by si Banker

What is it? Is there a fix for the fly wheels. I must say that the ac in my 964 is light years ahead of my 1987 and d I had spent a ton of money on it's ac system










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The lazy pedal is where it's reluctant to spring back up after depressing it for a gearchange....7/10 times it'll pop back ok, but the other 3/10 times the pedal stays partially depressed, needing you to hook your foot underneath to pull it back.

Having a read through some of my documentation (coincidentally, I'm also in the market to buy a C4, so am refreshing my knowledge), a single mass FW was used initially on the MY89 model C4, then a dual-mass flywheel on all "standard"(non RS, RS 3.8 and RSR) models from MY90 onwards, manufactured by Freudenberg for C4's and LUK for C2's MY92 onwards...

...This is where I have 2 sources of information, one with more detail than the other.

Streathers book states that Freudenberg manufactured a "modified" variant, used on MY91 to MY94 C4's and MY91 to late MY92 C2's (where it was then superceded by a LUK manufactured DMF). Quote "The Carrera 4 required a modified secondary mass assembly to solve the double mass flywheel failures of the 1990 model year"

The LUK DMF was apparently never fitted to C4's on the production line, but is approved as a retrofit.

From what I've read previously, there is no fix for a failed DMF, the remedy is to install a LUK unit (or a single mass FW, along with any mods needed to overcome idle stalling problems, which I know Steve Wong can cater for)

[paul284pt]

Hi,

Hood and engine release cables are prone to snap, it's worth checking them out. Later 964's had a secondary engine lid release behind light cluster.

Cheers,
Paul