Free guide · 1997–2005 · M96 flat six · 300–320 PS
Porsche 911 Carrera 996: what to check before you buy
What this car is, and the six questions that decide whether the one you are looking at is a good buy.
In this guide · 6 chapters
Who built it, and what they built
For twenty years this was the 911 nobody wanted, and the reason was the headlights.
In 1997 Porsche did two things that the faithful have never entirely forgiven. They replaced the air-cooled flat six with a water-cooled one, and they gave the car headlights shared with the Boxster — a shape that got nicknamed the fried egg and has been used as an insult ever since. The 996 was the car that saved Porsche as a company, and it spent two decades being the punchline.
Which is exactly why it is here. This is the last 911 an ordinary person can buy, and it is a real one: rear-engined, flat six, six-speed manual, the shape everybody recognises from thirty metres. What it asks in return is that you understand one bearing.
The engine
The M96 flat six, water-cooled, naturally aspirated, mounted behind the rear axle:
- 1998–2001: 3,387 cc, 300 PS
- 2002–2005: 3,596 cc, 320 PS
Six-speed manual (the G96) or the five-speed Tiptronic S. The manual is what you want.
One thing to be clear about, because it decides which guide you are reading. The GT3 and the Turbo do not have this engine. They use the Mezger unit, a different design with a different history: no sealed IMS ball bearing, and cylinder bores that are not commonly associated with bore scoring. Everything here is about the Carrera — Carrera, Carrera 4, Carrera 4S, Cabriolet and Targa. If you are looking at a GT3 or a Turbo, the bodywork and the age chapters still apply and the engine chapters do not.
And the one thing everybody has heard of
The IMS bearing — the bearing on the intermediate shaft that drives the camshaft chains. It is a small part that, when it fails, takes the engine with it. It gives no symptom you can feel or hear — at most, sometimes, metal glitter in the oil filter.
That reputation has done more to keep 996 prices down than the headlights ever did, and here is the part almost nobody knows: it depends on the bearing. Porsche fitted two different ones over the car's life, the change came over model years 2000 and 2001, and the reported failure rates of the two are far apart. The model year alone does not always tell you which one a car has.
That is the single most valuable thing in this guide, and the buying guide spends a whole chapter on it.
How the figures in this guide work
How much work each job is, not what it costs. Every point in this guide carries an effort — an hour or two, half a day, a day, two or three days, or a week or more in the workshop — plus a line saying whether the money sits in the part or in getting to it.
There are no prices, and that is deliberate. What a job costs depends on which country you are in and which workshop you walk into, so a figure I cannot verify is worse than no figure. If you want money, ask any workshop one question — what is your hourly rate? — and every hour in this guide becomes your own number, in your own currency.
None of this is advice about one particular car, because I have not seen the car you are looking at. Have every one of them inspected before you buy, by someone who knows this engine — and on this car, by someone who owns a borescope.
The six questions that decide whether this car is a good buy
More than on any other car in this series, the questions here are about evidence rather than condition. A 996 that drives beautifully can be three months from an engine. Six questions.
1 · Which IMS bearing does it have?
Porsche fitted two different bearings, with very different reported failure rates, and changed over during model years 2000 and 2001 — so the year alone does not always settle it. How to establish which one this car has is in the buying guide. And ask the second half of the question: has it been retrofitted? An invoice for an IMS retrofit is the most valuable piece of paper a 996 can carry.
2 · What does the over-rev report say?
The engine management records over-revs — Porsche calls the print-out the Vehicle Analysis Log — and the 996 has two ranges. Range 1 is 7,200 to 7,900 rpm, which Porsche itself describes as engine damage possible. Range 2 is over 7,900 rpm: engine damage probable. Porsche gives changing into the wrong gear on a manual car as an example of how it happens. When the entries happened matters as much as whether they are there, and how to read the log is in the buying guide.
3 · Has the oil filter been cut open?
Ask for the last filter, or for one to be cut open at the next service. Metal glitter in the pleats is the only warning an IMS bearing ever gives, and even then not always.
4 · Has it been borescoped properly — and what does properly mean?
Bore scoring is the M96's other known failure. An ordinary borescope inspection shows scoring once it is established, but can miss it early — and LN Engineering, who make replacement cylinders for this engine, recommend a more direct look where access allows. What to ask the inspector for, in so many words, is in the buying guide.
5 · Is there oil at the bell housing?
The rear main seal weeps at the joint between engine and gearbox. Not catastrophic, and it is normally done at the same time as a clutch or an IMS retrofit — which is why the sequence of jobs on this car matters as much as the jobs themselves.
6 · What has already been paid for?
On a 996 the folder is the car. The IMS, the clutch, the rear main seal and the coolant tank all leave no trace except on paper.
What the honest answer to all six looks like
A documented 996 — retrofitted bearing, a clean borescope done properly, a clean over-rev report — is an unusually cheap way to own something genuinely special, and the ordinary running costs are lower than its reputation suggests. An undocumented one is a lottery ticket with an engine attached.
And there is one thing this guide will not pretend to settle. There is a real disagreement about whether an M96 that has survived this long will keep surviving: the buying guides say yes, the engine builders who rebuild them for a living say no. That is unresolved, and it stays unresolved here — which is precisely why you buy on evidence rather than on an assumption.
That is only useful if you know what it is made of. The buying guide takes each of these six apart, adds the things that are simply twenty-five years old, and gives every one of them how much work it is, what tells you about it at a viewing, and whether it has to be done now or can wait years. It ends with a card you print and take with you, in the order you do it.
Which years, which specification
Built from 1997 to 2005, and the split you care about is not the facelift — it is the bearing, which changed over model years 2000 and 2001.
The two engines. 3.4 litres and 300 PS to 2001; 3.6 litres and 320 PS from 2002. The bigger engine is better and the difference is not dramatic; do not pay a lot for it. One thing cuts the other way: the two engines are not equally prone to bore scoring.
The 2002 facelift. New headlights — the ones from the Turbo, without the fried-egg indicator — a revised interior and the 3.6 engine. Visually it is the change everybody notices, and mechanically it matters far less than the bearing does.
Which body. Coupé, Cabriolet, and the Targa with its big sliding glass roof. The coupé is the one to have; the Cabriolet adds a roof mechanism and, on earlier cars, a plastic rear window that hardens and cracks; the Targa adds a complicated glass roof and the leaks that come with it.
Carrera or Carrera 4. The four-wheel-drive car adds a front differential and driveshafts, and takes away a little of the rear-drive feel that is the reason to buy a 911 at all. Neither is wrong.
And what is out of scope. GT3 and Turbo. Different engine — the Mezger — and a different guide.
What to establish per car:
Which bearing it has. First, always.
Whether the IMS has been retrofitted, and with which kit.
Whether it has been borescoped, and how.
The over-rev report, range 2.
And how it has been serviced. This guide's advice on oil changes is firm, and more frequent than the interval a Porsche dealer lists for the 996.
Beyond that, look for a car nobody has modified. Factory wheels, standard ride height, the original exhaust. On a car that spent twenty years being cheap, an unmodified example means an owner who understood what he had.
What it is worth
This is the hardest thing to establish on your own and it does more than anything else to decide whether you buy well. I am not going to give you a price list — it varies by country and by month, and an out-of-date number is worse than no number. I am going to give you the method.
On a 996, you are not pricing a car. You are pricing a folder. Two cars with the same mileage, the same colour and the same condition are not worth the same money if one has a retrofitted bearing, a clean borescope and a clean over-rev report and the other has nothing. And the market still frequently prices them as though they were, because it prices 996s on the headlights.
There are three kinds of car for sale, and each deserves a different offer.
The documented car. IMS retrofitted with an invoice, borescope report, over-rev report, frequent oil changes. Top of the market, and on this model the only version that lets you sleep.
The tidy car with no paperwork. Drives beautifully, looks lovely, owner says it has never missed a beat. This is the dangerous one on a 996 specifically, because everything in this guide is invisible until it is terminal.
The project. Known work and a price to match. Be careful here in a way you would not be with a cheaper car: a 996 needing an engine is worth less than nothing, and "needing an engine" is a state you can arrive at from "drives perfectly" in one afternoon.
How to set them against each other. Take the asking price, add a specialist inspection with a borescope — which on this model is not optional and is the best money you will spend — and add the retrofit if it has not been done. Call that the entry price and compare entry prices.
And one honest note about the market. 996 prices have been rising, because people have worked out that it is the last affordable 911. The consequence is that the cheap ones are now cheap for a reason, and the reason is usually in this guide.
Where to look: the Porsche specialists first, then the big classified sites, then the auctions. And follow the market for a month before you go and see anything, because on this car you need to be able to tell an ordinary price from a suspicious one.
What it is actually like to own one
It is smaller than you think, and it feels like a 911 immediately.
The engine is behind you and you can hear it doing its work — not loud, not theatrical, but always present and always slightly to the rear of your ears. The steering is hydraulic and it tells you things that no modern car tells you. And because the engine is where it is, the nose is light and the car turns in with a directness that you do not get used to.
And it is usable in a way an air-cooled 911 is not. The heating works. The air conditioning works. You can drive it in February. It has a boot at the front and two seats behind you that will take luggage or, briefly, people. This was the 911 that Porsche made properly liveable, and that is exactly what the purists held against it.
What it costs you in attention. More than the money: it costs you diligence. Frequent oil and filter changes, without exception. A specialist rather than a general garage. And the discipline to have the borescope done rather than assume, because on this engine an assumption is the expensive option.
And it is cheap to run in the ways people do not expect. It is light, it is not thirsty for what it is, brakes and tyres are ordinary sports-car money, and the interior is built to last.
What it gives back. A real 911 — the shape, the layout, the noise, the steering — for a fraction of what any other 911 costs, from an era when Porsche was still a small company that had to get it right. That is not an investment and you should not call it one, even though the market has started behaving as though it is. It is the cheapest ticket into something that no longer exists.
The buying guide — €24
Everything above is what the car is. This is what you check.
Ten faults that belong to this engine, taken apart one by one, with how much work each repair is and how to tell which of them you are looking at. Thirteen things that are simply twenty-five years old, every one with how much work it is, what tells you about it at a viewing, and whether it has to be done now, within a year or two, or not at all. Why this car does not really rust, and the two places where water and leaves collect instead — one of which nobody looks at. The IMS bearing and bore scoring: which bearing your model year has and what that does to the odds — and the two model years where only a look at the bearing tells you — how to read an over-rev report, and the one sentence that makes a borescope inspection worth paying for. The viewing in fourteen steps, including the two moments that come only once. The sentences you say to the seller, and how to build an offer out of what you found.
And a card you print and take with you — fifty-two lines, in the order you do them. That comes as a separate file, because nobody wants to print a whole guide to take a few pages to a car park.
This is what one of the thirteen looks like
1 · The battery, and where it lives
An hour or two · expensive part for what it is, easy access The battery sits in the front boot. That matters for two reasons: a weak one produces odd electrical behaviour across the car, and a leaking or badly vented one corrodes the compartment it sits in. How you notice it: slow cranking after the car has stood, and staining or corrosion on the tray under the battery.
Do it if the battery is old or of unknown age, and look at the tray while you are there.
And this is how the card reads
- 1 · The over-rev report · ideally before you travel
- 2 · The cold start · stand beside the rear wing
- 3 · The engine, such as you can see it
- 4 · Under the back, with a torch
- 5 · The nose · the step people skip
- 6 · Round the outside
What €24 buys, put next to what it saves
The bearing is a small part and the consequence is the engine. The two bearings Porsche fitted have very different reported failure rates — and on most model years you can tell which one a car has, for free, before you leave the house. The guide is €24. It will not stop any of that from being needed — but it does tell you which of them you are looking at before you agree a price, and that is the whole of the difference between paying for a car and paying for someone else's postponed maintenance.
Why there are no prices in it
Because a price we cannot verify is worse than no price, and because a price would be wrong for most of the people reading this anyway. Workshop rates across Europe differ widely, and so do parts prices. A quote from a specialist in one country tells you nothing in another.
What does not change is how much work a job is — that follows from what has to come off the car. So every point in the guide says whether it is an hour or two, half a day, a day, two or three days, or a week or more in the workshop, with a labour figure where a source gives one. And it says whether the money sits in the part or in getting to it, which is what lets you tell a fair quote from a bad one.
If you want a figure, ask any workshop one question — what is your hourly rate? — and every effort level in the guide becomes your own number, in your own currency. One question, and the answer is actually true for you.
How this guide was put together
Because you should know before you pay for it.
- Every fault and symptom comes from a source the guide names, the manufacturer's own documents first. The effort levels are our assessment, unless a source gives the hours.
- Where the sources genuinely disagree — whether an M96 that has survived will keep surviving — it says so and leaves it open, instead of picking the comfortable answer.
- The effort of every job is counted item by item and checked against the list before every edition.
- It says as plainly what you can leave alone as what you have to do. Three of the thirteen age points start from leave it.
Leave your email address at the checkout and both files arrive straight away: one guide and one card, as two pdfs. No subscription, no account.
The full guide · €24
24-page guide, A4 and phone · 4-page inspection card · instant PDF · VAT included
Have every car inspected before you buy by someone who knows this engine. This is general information about the model and not advice about a specific car.