The secret to M96 (Porsche 996/986) ownership

"JasonStern911" (JasonStern911)
02/16/2018 at 20:04 • Filed to: None

I’ve posted variations of this in comments multiple times, so I’m just going to make a full post once so I can link to it in the future.

The secret to owning any M96 powered Porsche is to factor in an extra $3k. After purchasing the car, go to a reputable independent Porsche mechanic and have the following work done:

* LN Engineering IMS bearing retrofit

* Air/oil separator replaced

* Water pump replaced

* V-belt replaced

* Spark plugs replaced, coil packs tested

* Rear main seal inspected and, if original (doubtful at this point), replaced

* Misc. gaskets inspected and replaced on a need basis

* MAF sensor cleaned

* Fresh air filter, coolant flush

Depending on the miles and transmission type, consider replacing the clutch as well.

Do this all at once to greatly reduce labor costs, as dropping the engine once is considerably cheaper than dropping it multiple times should individual parts fail during ownership. Do this and not only should you have a car with a powertrain that only needs basic maintenance for the next 50k miles, but you’ll have the peace of mind in knowing that all of the common powertrain problems have been addressed.

DISCUSSION (9)

JasonStern911 > JasonStern911
02/16/2018 at 20:17

Other advice:

* Don’t even consider buying one without a pre-purchase inspection.

* Invest in a magnetic oil drain plug. Cut open used oil filters and inspect for any debris. Send an oil sample to Blackstone Labs for oil analysis every oil change. Use a high ZDDP oil. Change every 5k. Especially do all of this if you’re willing to take a chance on the factory IMS bearing.

* A Durametric scanner will likely pay for itself over time, especially if you end up owning multiple Porsches.

JasonStern911 > JasonStern911
02/16/2018 at 20:26

“I’m not going to spend $3k immediately after buying a used car - especially a Boxster that is only worth $5k!”

That’s fine. There are plenty of other cars out there that are more reliable if reliability is a main concern. And there are also plenty of cars out there that seem like they should be incredibly reliable but also suffer from some design flaws (i.e. MR2 Spyders and their pre-cats) because building a car is hard. Base model 986s were still $40k cars new and base model 996s started in the high $60ks. There’s a reason these cars have depreciated. And what’s great about that is that the cars are old enough that all of the common problem areas have been identified, fixes are known, and there is an amazing amount of support at forums like Renntech.

JasonStern911 > JasonStern911
02/16/2018 at 20:28

“Can’t I wait until something breaks and deal with it then?”

Yes. That is a perfectly valid option. Just realize that IMS bearing failure is still a risk that could potentially grenade the vehicle’s engine, and odds are that engine is worth more than half of the value of the car. Most forums predict IMS failure at about 5% for the later single-row bearings and under 1% for the early dual row bearings.

Dr_Strangelove > JasonStern911
02/16/2018 at 20:31

This is a good starting list, however, I paid $3,500 to have an IMSB retrofit and clutch done at the same time on a 2003 Carrera, and that was all I had done. $3,000 for your entire list at any reputable Indy is highly optimistic. I think your list may be DIY-able for $3,000.

Also fair to mention that your list covers preventable maintenance from a replaceable parts standpoint but there really isn’t a way to address the M96's other famous failure points such as cylinder wall cracks, bore scoring, Cylinder 1 D-Chunk, camshaft and timing chain pad material failure, just to name a few.

As a 996 owner, my advice is to bring your wallet and learn to DIY, regardless. If you’re not going to DIY, bring two wallets.

JasonStern911 > Dr_Strangelove
02/16/2018 at 20:47

A dual row IMS retrofit kit from LN Engineering is $800. A clutch kit is $650. $3,500 would mean roughly 20 hours of labor at $100/hour. Dealerships usually only charge 5 labor hours (at a much higher labor rate) for a clutch replacement. IMS bearing replacement labor varies, but I don’t recall it being too much at my local independent Porsche mechanic, as they had already done several and thus had the job down. You do bring up a good point about consulting multiple shops before committing to any work as prices can vary heavily.

As for the other M96 weaknesses, I’m not going to defend the M96. But I will state that neither my previous 986 nor, knock on wood, my current 996 have experienced any such problems. If the failure rate was that common, it seems odd that Porsche would have kept the M96 in production for over a decade.

Neil drives a beetle and a fancy beetle > JasonStern911
02/16/2018 at 21:52

Fuel filter replaced.

Crank position sensor on the ready.

JasonStern911 > Neil drives a beetle and a fancy beetle
02/17/2018 at 17:03

Didn’t consider the fuel filter as I was mostly focused on work that should be done with the engine dropped, but good call. Easy replacement at least on the early 986/996 models. At least not something requiring paying a shop to do.

JasonStern911 > Neil drives a beetle and a fancy beetle
02/17/2018 at 17:04

Also not familiar with any crank position sensor issues. Any idea how frequently they fail?

Neil drives a beetle and a fancy beetle > JasonStern911
02/17/2018 at 18:14

I don’t know, I had one go and when I was researching it seemed like a pretty common issue. They can cause intermittent no-start issues.