Looking at buying a 996 Turbo and was wondering what problem areas I should be on the lookout for? For instance, the IMS bearing on the early 997's was an issue. What mistake could I make?

 

As long as the car is in good shape, good maintenance records/evidence it has been maintained by the owner, there really isn't that much to be concerned with.. These cars are quite stout. Having just bought mine, here's what I looked for...

2nd gear pop-out was my biggest concern.
The hydraulic wing is prone to failure.
Vacuum leaks (should be found in PPI).
Oil pressure sensor can be a little wonky at times, reads incorrectly.
Secondary air pump commonly throws a CEL (PPI should find)

Really as long as the car is well kept, in good shape and drives properly, if it passes PPI and doesn't pop out of 2nd gear, the other potential issues shouldn't make it a no-go and rather be used as negotiation points. I was able to get the dealer to come off $6k on my purchase because it had a few relatively minor things that this dealer didn't want to deal with due to potential cost once I pointed it out (independent dealer, little/no Porsche experience).

 

http://porsche996turboblog.blogspot....sues-list.html

have a look at this link, it outlines some things to look out for.

 

2nd Gear Pop Out (Evident from high RPM Decel)
Wing Hydraulics
Coolant Fittings (Best to find a car that has already addressed this)
Clutch Hydraulics (Best bet is a car that has converted to GT2 slave)
Front Radiators can deteriorate due to debris (mostly leaves) accumulating in front of them.
IMS is a non-issue with the GT1 block

If you are looking for a modified car
Stock clutch is only good to light modifications. Upgraded car should have beefier unit
Stock rods are good to around 600whp. Anything more needs updated
Stock injectors are good for light tunes and exhaust. Any updated turbos need larger injectors (5bar FPR is a bandaid, look for injectors)

 

This should be a sticky in this section for those looking for information on what to look for..
Nothing against the OP of course but we see these threads all the time now that people are realizing what a bargain the 996TT is and its potential.

 

The 996 Turbo is just a used car so you have to be on the look out for any problem. Focus on 2nd gear popout and possibly over look a diff fluid leak and well, that's a mistake you could make.

My advice is visit the car cold and with the A/C off -- you test the A/C heater later -- turn the key on and confirm all the warning lights come on -- especially the CEL! -- and go off when the engine starts and runs.

Let the engine idle while you walk around the car looking at body panel finish, fit, etc. But keep an ear tuned to the engine. While it can sound a bit gruff it should smooth out soem as the cold idle RPMs drop to near the hot idle RPMs.

What you do not want to hear are distinct ticking, knocking noises, regular or irregular. Groaning/growling noises can be the water pump, power steering pump (low on fluid), or the serpentine belt idler roller/tensioner bearings.

Even perfectly healthy these engines are a bit noisy but you are on the look out for out of the ordinary, abnormal sounds. Go check out a few Turbos. When you come to one with a noisy engine and you will you'll recognize it and know what to listen for.

Have the seller take you on a 15 mile test ride. The route should give the driver a chance to demo the car as you intend to use it. Pay attention to how the car is driven. For instance does the driver skip 2nd going instead from 1st to 3rd, or does he make 2nd a real short gear leaving his hand on the shifter? Could be a sign of 2nd gear popout problems so be sure you test for this. 'course, you test to make sure there is not any pop out in any gear.

Back at the starting point then you take the car out and drive the same route and drive the car the same way, but of course as I touched upon above not exactly the same way if there were indications the seller was driving in such a way to avoid problems.

Once fully warmed up the engine should pull hard from just off idle all the way to redline and an up shift should have the engine resume its pulling. Afterwards the engine should return to a normal hot idle with no drama.

With a manual try to arrange flooring the gas pedal in 4th or 5th gear at 2500 RPMs to check for clutch slippage.

For a Tip execute a K u-turn. This has you shifting the transmission from reverse to drive to reverse adn drive in rapid succession. The Tip should keep up and there should be no protest or clunking or lurching when movng off. Underway the upshifts and downshifts should occur when they are supposed to and be smooth.

In short you want to experience the car in its natural state with the engine running and the car on the road being used as you will use it.

After the test ride and drive then give the car a used car check out. Assume nothing works until you confirm it does work.

Some highlights: Check for moisture in the carpets, along the door bottoms, and under the seats. Check the body water drains are clear of trash. Radiator ducts likewise. Work the spoiler manually -- button on the dash -- a few times then open the engine compartment lid and check the spoiler hardware for leak sign.

Check the A/C and heater controls all work. Check the power seat controls. Check/test everything. The 111 point check list the techs use to CPO one of these cars is a good list to work from. You can't do all the tests/checks but you can do a lot of them.

Be careful. A dark headlight may be a bulb. But it could be a bad igniter. A bulb is espensive enough but the igniter lists for nearly $1000 though there are cheaper sources compared to the dealer parts counter.

After all of the above if you stil like the car and believe you can buy it for an agreeable sum arrange for a PPI. Among other things this gets the car in the air and a close inspection can be made for any leak sign. Any gasket, seal, o-ring, hose, hose fitting, hydraulic line or line fitting dust boot is checked for leak sign. If you focus on the "biggies", RMS and water pump, you may miss coolant hose fittings leaking (engine out job), or front diff axle flange seals or any number of leaks rather far removed from the water pump and RMS but expensive to put right nevertheless.

 

Check boost on dash, .9? is normal unless it's an x50 car I believe? Others can correct but you want to look for low boost or high boost. One is a sign of leaks or issues, the other a sign of a tune. If it has aftermarket exhaust cruise it around 2400rpm or so and listen for drone - this can be head splitting on these cars! If it has an exhaust check for catalytics and make sure a PPI is done that includes emissions and overrev.

 

.7 is about "it" max on an unflashed k16 car. w a spike of .9 *maybe* on k24 car. if my addled memory still serves lol. .8 on k24 though means all is working as it should.

there must be a 1000 threads on the most common problematic issues. what you dont find here by searching and whats already above? try a google search which strangely brings up 6spd threads that the internal search here wont even find. it's strange but true. GL with your search..for threads AND the car lol

 

Thanks to everyone for very helpful, and thoughtful, inputs.