My non computer literate friend has a 993 TT with a Fabspeed exhaust and a remapped computer, with 80K on it. What common problems are you guys seeing?
He's worried about a top end rebuild and turbo failures, I'm not sure what's happening with these cars, can you help me?
He's thinking about selling the car before he has to foot the bill on any major repairs.

 

As long as the car is meticulously serviced it keeps going. Porsche owners have them serviced or DIY. Either way it is more expensive if you abuse it.

Drive it right (tame and spirited) and service it as scheduled.

Bad signs are eExcessive smoke on start up may be the valve guides. The total oil consumption per mile is an indicator too. Can have leakdown and compression test done as well.

But he should have done all this before buying it, so yes it may be too late already. For him it may be best to sell. Not for any other reason than the car can go to someone who will service it and pass it along for the next owner before its tired.

Not being too harsh just know they need schedulled maintenance. If you want to drive fast you look forward to having it serviced knowing it is sorted.

Regards,

 

He's had the car for 30,000 miles, and it is well maintained, he is concerned about common failures that seem to be a pattern ie: most 993tt's need a new x at 80,000 miles, a lot of them need a y at 100,000 miles, etc.
I think that most smart people who have expensive cars understand that excellent maintainance is the key to avoiding catastrophic failures.
I was at a Porsche shop last year, they had about 10-12 cars there, and 3 of the cars were 993tt's that needed new turbos. This indicates a possible pattern to me.

 

Just run a compression and leak down test on it to determine the state of the engine. Then he will know what might need to be done.

 

people replace their turbos for several reasons:
1). the seals just wear out and start passing oil. This is exacerbated by not allowing enough "cool-down" time. Its not unusual to need the turbos rebuilt at about 75,000 miles, but there is a large variability depending on the type of driving and the cool downs. Rebuilding the turbos back to stock is not very expensive.
2). during an oil change, the wrong (Mahle) oil filter is used (or the proper Porsche filter put on too tight), and oli leaks into the turbo. This is often diagnosed as a bad turbo. Its not, if the source of the oil is fixed right away.
3). 993TT owners are nuts, and want more and more HP. An easy way to start is with beefier turbos.

So... not all turbo replacements are done because of legitimate failures, and rebuilding turbos is not expensive (unless you go for the big HP units)

Another potential issue to worry about is valve guides... this is a really expensive problem, but can generally be seen with excessive oil consumption, bad compression numbers, and in some extreme cases, a noticible reduction in HP. IMHO

 

Another place to look is the suspension. Original shocks are good for 50k miles or so. If his car still has factory shocks, he should be prepared to replace them. However, I would not count that as a failure item.

CP

 

Some normal failures that I'm aware of:

- MAF sensor
- you need to have all the ignition bits replaced by now (plugs, wires, distributor); otherwise he's probably running on quite a few ponies less than the adverised 400+.
- intercooler hoses
- clutch slave
- turbos (as discussed above)
- stock shocks don't last very long (as mentioned above)

 

The MAF sensor is something new that I've been seeing lately - makes me wonder about the after market air filters people are putting on.

Ignition stuff - normal for any car.
I/C hoses - normal - they were originally recalled and upgraded.
turbos - as discussed above - if you do a good cool down routine every time they will last.
Shocks - they were crap and the rears actually fail at about 30,000 miles (at least around NYC) - they were originally Monroes, and the Bilstein replacements are truly AMAZING!

One thing most people do is remove the engine under tray - helps increase cooling and you find out more quickly if you have an oil leak.

Other stuff -
AC condenser fan balast resistor and oil cooler fan balast resistors tend to go bad.
The little light behind the digital display in the tach - 35cents but you have to remove the steering wheel, stalks, etc to get it out.
Check your fan idler bearing they tend to go and fry the alternator - if you can replace the system with the single belt setup - similar to the RS - I'd recommend it.
My clutch slave wasn't bad, but after all these years the pressure accumulator was - I replaced that and all is well so far.

These cars are well engineered and should last a long time if they are properly maintained and not abused. Remember that this is the culmination of all of the engineering that started in 1963, so it is fairly well perfected. One drawback is that because the fundamental setup is so old, the car is very much like a swiss watch in that multiple systems are layered over one another making a simple repair tedious and complex due to the removal of all of the stuff around the area.

 

I have a question about the cool down required. I've read on here that you should let the car idle for 2 minutes after a hard drive. Should you let the car idle for 2 minutes, or another lesser amount of time, if you say take a trip to the grocery store or commute in the morning.

I'm looking at buying a 96' with 40K miles. Is it a good idea to just go ahead and replace the ignition parts, hoses and MAF and shocks? In my case the shocks are stock and probably everything else.

 

Not being rude (I have asked my share of Q's) But use the search feature because there are quite a few threads on this. SOme say don't worry about some are religious about it.

 

Bus,

The amount of cool down depends on how you've driven the car, and how hot you've gotten it. I'd let it idle for 5 minutes after a 20 minute hot lap session at the track. I'd let it idle for 2 minutes after pulling off the freeway into a gas station. I'd let it idle for a minute minimum in most other, less stressed occasions. I always let me car cool down while I'm getting the car cover on... I switch it off as I'm getting readyu to cover the roof part. In my garage I let it cool down while I unload stuff or give it a quick wipe down. I dunno... its never too inconvenient for me.

On a 40k car, the shocks for sure will be toast. You may find yo9u can manage ok with them, but you'll be a lot happier with a decent setup. Most guys switch to lower springs or coil=-over adjustables "while they're in there" because its a labor intensive job, and you'll onl;y want to do it once. You'll also need a corner balance and alignment (all 4 wheels) when you;re done. Don't skimp on this.

I wouldn't worry about any of the other stuff you mentioned unless there were symptoms of failure.

 

Yeah - I agree with Steve. This whole thing with the MAF sensor is a bit rediculous. I think it is due to the K&N type cone filters that people are putting in. Also - don't worry about the hoses and ignition stuff. I would recommend that you get a fresh set of belts though.

 

This is what I've replaced on my car, either as an upgrade or due to worn parts:
- Clutch (worn)
- Suspension (upgrade)
- Divertor valves (upgrade)
- Lifters (one was totally gone, the other exhaust ones were tired, intake looked good)
- Spark plugs (worn)
- Valve cover gasket (leaking)
- Slave cylinder (seal worn)
- Accumulator (seal worn)

Other than that, just routine maintenance. When I compare this to my 475hp 2.0L racecar, the 993 is amazingly cheap to run. The Talon requires endless maintenance and can barely maintain it's 475hp unless the temps are good out and I run race gas. In comparison, the 993 runs 408hp all day and night and has always finished every lapping day with the driver more tired than the car.

 

Gee, thanks for dismissing my recommendations; I happen to know for a fact that the electrics go South over time. My car, at 34K miles and completely bone stock was definitely not putting out the advertised power. After replacing the MAF and the ignition electronics (per Kevin's suggestion), the power was back.

 

interesting..
bump