GC996

With all due respect, here is the best advice I can give anyone who owns a 996 and can't stop belly aching. Now may be the time to sell it. Prices have gone up. Take your money and buy a Honda. You will be happier.​​​

If you own a 996 and are looking to share ideas with like minded folks to improve your 996, keep posting on the forum. It's awesome. Thanks for the value you add.

If you don't own one and are lonely and just looking to talk to someone, go join the Honda forum.

frederik

Agreed, the way to successfully own a 996 is to maintain it properly, but not worry too much beyond that. And don't read this forum.

nrp3

I don't know enough about these to wonder whether at the time the motor was a radical departure in technology or materials (aside from being liquid cooled), or whether the companies financial situation when these were conceived forced them to cut corners. I get the impression that a lot of these cars, not just Porsche, suffer from some issues, have expensive maintenance, etc. I knew that coming into this. I can safely say my 2016 Town and Country van is probably better made in a lot of ways. So is my work van. Different vehicles with different purposes. That said, I'm looking forward to a new year of investigating its condition more deeply after doing a lot of reading. Wherever it leads it leads. New injectors and one of those UOAS systems are the two likely candidates, though dropping the pan and looking at the bores as well as doing some more investigation about IMS and RMS condition are on the list too. Being a tip, I'm trying to come up with a logical order to do this so I'm not dropping the motor and or transmission twice.

Charles Navarro

Correct. Anyone who has rebuilt a Porsche with nikasil bores knows that if the engine is running rich that the bores will wash down, glaze the bores over, and take out the piston rings. This is why we mandate new injectors are fitted on rebuilt engines, along with a new MAF and primary o2 sensors at bare minimum. Those who know smoke test their intakes and check for vacuum leaks that can negatively affect fuel trim and increase wear. Seen too many instances where parts get reused when they are the reason why the engine failed the first time. Not enough money to do it right the first time but plenty of money to do it twice.

Charles Navarro

I'll just add that Porsche is the only automaker to ever use Kolbenschmidt's Lokasil process and only on the M96/M97 engine from 97-08 in Boxster, Cayman, and 911 models. No manufacturer has used this process since.

wildbilly32

...or get/keep both! Best of both worlds.

NYoutftr

The more I read on bore score, the more confused I get.

It appears that every M96 that has been scoped has some degree of bore score ?
True or False?

Does anyone have images of cylinders with 60k or 70k miles on them with no bore score?

This gradient of bore score, is any bore score acceptable or do cylinders have to look fresh for a M96 to be free of immient bore score?

Are all M96s going to fail from bore score?

Other 996 forums world wide, of which there are many with thousands of members, (obviously with some redundancy) don't seem to have as high a percentage problematic M96 engines as on Rennlist.

How does a M96 last 150k miles plus with no problems other than regular maintenance?

ZuffenZeus

David, join the free webinar LIVE on YouTube next Thursday and ask these questions. These are really good thoughts. I've become friends with Hartech's main rebuilder (Lee Jenkins) on Facebook and he reports daily. He rebuilds many M96/M97 engines every week and says that cylinder bore scoring is the main problem they see with these engines. We're planning on doing a Rennvision webinar with Barry Hart and Lee Jenkins soon. Barry brings a wealth of proven experience with Porsche engines to the table. Stay tuned! I would like to invite you to become a Rennvision member!

blacksquid

This interesting for me as my 1999 m96 has just been delivered to FSI for a rebuild and there is no mention of new injectors being included in the proposal. I'll ping FSI.

abossana

As these cars age its likely that the ownership will change hands and the buyers will start becoming a more enthusiast based breed. During the early years of ownership the dealers take care of the issues and the owners just drive the cars and trade them in when done. When the cars start becoming vintage you will start seeing people who want to preserve the car and bring them back to their original state. Its not just a Porsche thing. During this process problems will be found an that's when Forums provide a wealth of knowledge but they also typically attract people with problems that need answers. I would be willing to bet that majority of 996-997 owners who don't read the forums have a very low stress ownership experience.

plpete84

That is a very good point that I was thinking about. I don't care for an increase in power/displacement and would potentially consider an RND engine as a rebuild option. Looking at the list of what the build includes I also didn't see any mention of new injectors. If auxiliary parts like AOS, spin-on filter adapter and filter, oil filler tube are included then why not injectors, if they are such an important piece to the puzzle. Hope Charles can chime in.

Thank you for saying this! Is it an unavoidable fate or does following the recommended steps can really help prevent bore scoring. I'd also like to better understand the difference between minor scuffing on cylinder walls as compared to scoring. What's acceptable and what's not. We often see the advanced scoring examples but there have been several examples posted here and in 997 sections showing minor scuffing. Yes - will be joining the webinar!

cdk4219

If you build it like a 2 stroke plated dirt bike cylinder, it’s probably not going to last as long as it could. As for the sealed bearing inside the engine, the same applies. All or nothing with rebuilds on these engines, and the costliest seems to be cylinder reworking. Lots of nonsense from these two items. Don’t forget lots of other Porsche engines suffer from this cylinder damage.
I remember in my dirt bike days, the concern with cold seizure, running a 2 stroke hard before thoroughly warming it up, and it was definitely a problem. When those cylinders and pistons went south it was bad as well, and not replacing bearings and seals was regularly done but not the greatest idea.
The 996 has a great chassis , great suspension and brakes, but the Achilles heel is the engine and cooling system problems IMO.

996AE

On a recent build I did pay for all injectors to be cleaned and tested before placing back in car. Engine builder said no reason to replace if test was good after cleaning.

With out removing can you test injectors?

Sorry if a silly question

Nico911

I've owned two 911 in the past, thank you very much !

Charles Navarro

Originally when the RND program was developed for SSF, it was planned that an install kit would have to be purchased for there to be a warranty, but that never happened. What was supplied with each engine was determined by SSF. There are plenty of other items that also need to be replaced that are not included like flywheel, clutch, flywheel bolts that isn't traditionally part of a longblock. The reason why the AOS was eventually added to what was included was because shops were using non-genuine ones that were failiing; same with the oil filler tube and even the oil cooler itself after SSF had shops again reuse these items and cause damage to the rebuilt engine.

However, injectors have always been recommended as part of the RND installation directive but the reason we don't include them is that shops want to source them and sell them to the customer directly, so we let shops handle purchasing these parts and other components required for installation.

Since all RND Engines come standard with an IMS Solution, they would have the spin on oil filter adapter and spin on filter.