996 engine reliability
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Brucey
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996 engine reliability
Hiya all, I'll apologise in advance if this has already been done to death but as I'm always aspiring to own a 911 and 996 prices are ridiculously low at the moment the question is "are the engine reliability issues I have read about on the internet really that bad and will it literally be a gamble buying one" I have spoke to a Porsche mechanic who reckons it's one off the bench and one back on again on a daily basis.
I'd really appreciate your thoughts on this as I really value your opinions. Thanks alot.
Andy Bruce.
I'd really appreciate your thoughts on this as I really value your opinions. Thanks alot.
Andy Bruce.
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sam
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Re: 996 engine reliability
should think most cars have been fixed by now, as I think it was an early car problem, although the engine problems did not help the 996's reputation, and coupled with the huge quantity of cars made, the prices are very reasonable as there are a comparitively high number on the market. suppose there is still a higher risk on these engines compared to other 911's though.
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Sean Smallman
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Re: 996 engine reliability
The values take into account the engine failures, they are one heck of a lot of car for the money.
If I bought an early 996 I would put £5k in an ISA and forget about it, just in case.
The 964 values suffered years ago because of engine issues. It is not mentioned these days and values reflect this.
If I bought an early 996 I would put £5k in an ISA and forget about it, just in case.
The 964 values suffered years ago because of engine issues. It is not mentioned these days and values reflect this.
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Lee 944
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Re: 996 engine reliability
Is it not the same engine as your Boxster Brucy? If they are the common, finding one that has already had its engine repaired by Hartec in your area should be quite easy. However, I dont think it is the issue it is made out to be. Cars that have had a clutch, should have had a new seal fitted, removing the problem. 
Lee.
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village eejit
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Re: 996 engine reliability
This poll on Piston Heads will give you a lot of info. The rear main seal isn't really a common cause of engine failures, not relative to IMS bearing failures or bore liners anyway.
The figures look to back up other reports I've seen with about 10% failure rates.
http://www.pistonheads.com/gassing/topi ... rebuild%3F
The figures look to back up other reports I've seen with about 10% failure rates.
http://www.pistonheads.com/gassing/topi ... rebuild%3F
Steve
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Brucey
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Re: 996 engine reliability
Hiya lee, yeah apparently it is virtually the same engine mate but I've been told the 2.5 engine I've got never really presented any problems whereas the 3.2 did. Again this is just what I have heard and it may well be untrue but if I was to spend £9,000 - £10,000 on a 996 I want to be able to enjoy driving it without thinking "what was that noise" every two minutes and worrying about impending doom.Lee 944 wrote:Is it not the same engine as your Boxster Brucy? If they are the common, finding one that has already had its engine repaired by Hartec in your area should be quite easy. However, I dont think it is the issue it is made out to be. Cars that have had a clutch, should have had a new seal fitted, removing the problem.
- tr7v8
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Re: 996 engine reliability
Just debating this with my new Boxster! If you start reading the forums you'd be in the asylum within an hour or so.
As I understand it there are 4 problems with the M96 lump.
1. RMS failure, this generally seems to result in an oil leak which normally is just "sweating". This can be fixed when the clutch next gets done. Not on a Tip obviously
2. D Chunk, or liner failure. This was an issue with early 2.5s, as I understand it not seen on later engines.
3. Bore scoring & ovality. According to Barry at Hartech this is an ongoing issue. Just seen an 08 plated car with scrap crankcases because 4, 5 & 6 bores looked like a file had been run up them. Localised overheating & too long between oil changes would be my guess. I'll be doing more oil changes than one a year! Also regular coolant & waterpump changes, possibly running water wetter & never driving on if it overheats.
4. IMS failure. Been researching this to death over the past few days. More regular oil changes & not driving like Miss Daisy look to assist with this. The LN bearing seems like a good change as well. Autofarm charge £ 1450+VAT on a Tip. The bearing is around $350 & the tools are around $150ish. Maybe this is a job I'll do myself. The tools can be passed on/rented/sold afterwards. The only issue is changing the RMS at home at the same time? Looks to need a special tool, can this be bypassed?
I might add these are my views from what I've researched over the past few months.
As I understand it there are 4 problems with the M96 lump.
1. RMS failure, this generally seems to result in an oil leak which normally is just "sweating". This can be fixed when the clutch next gets done. Not on a Tip obviously
2. D Chunk, or liner failure. This was an issue with early 2.5s, as I understand it not seen on later engines.
3. Bore scoring & ovality. According to Barry at Hartech this is an ongoing issue. Just seen an 08 plated car with scrap crankcases because 4, 5 & 6 bores looked like a file had been run up them. Localised overheating & too long between oil changes would be my guess. I'll be doing more oil changes than one a year! Also regular coolant & waterpump changes, possibly running water wetter & never driving on if it overheats.
4. IMS failure. Been researching this to death over the past few days. More regular oil changes & not driving like Miss Daisy look to assist with this. The LN bearing seems like a good change as well. Autofarm charge £ 1450+VAT on a Tip. The bearing is around $350 & the tools are around $150ish. Maybe this is a job I'll do myself. The tools can be passed on/rented/sold afterwards. The only issue is changing the RMS at home at the same time? Looks to need a special tool, can this be bypassed?
I might add these are my views from what I've researched over the past few months.
Jim
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Lee 944
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Re: 996 engine reliability
All good points Jim. One thing that struck me about the failure threads on PH ( who aren't exactly the brain trust, are they? ) is the fact that you never hear about the ones that run fine and never fail. If you look at the production numbers, I'm sure the problem is smaller than the internet has made out. I know some very well educated, knowledgeable Porshce enthusiasts who have still went ahead and bought a 996, once armed with all the facts. I had looked at several 996C4S cars during my search and would have bought one if it had been the right spec'.
It would be good to see you write up the DIY repairs Jim. Like I said, I think these cars/engines will be in the hands of ex 944 owners in the next few years.
It would be good to see you write up the DIY repairs Jim. Like I said, I think these cars/engines will be in the hands of ex 944 owners in the next few years.
Lee.
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Lee 944
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Re: 996 engine reliability
O/T.
One thing to add Brucey, child seats fit in the rear of a 911. Might help Mrs Brucey free up more capital if there is a family outing on offer?
One thing to add Brucey, child seats fit in the rear of a 911. Might help Mrs Brucey free up more capital if there is a family outing on offer?
Lee.
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Brucey
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Re: 996 engine reliability
Lee 944 wrote:O/T.
One thing to add Brucey, child seats fit in the rear of a 911. Might help Mrs Brucey free up more capital if there is a family outing on offer?
In all honesty I love the Boxster and will probably keep it as we are looking at moving to Ramsbottom and with an increase in mortgage payments it would be hard to justify getting a loan for a 996 but on the other hand I keep thinking when I move to Rammy I could stick a few grand on the mortgage to cover it! One things for sure I'll be pestering the lads at Porschapart alot more.
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Brucey
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Re: 996 engine reliability
Hiya Jim, thanks for your reply. I must admit I have also thought of getting a 3.2 986 as this would be a more financially viable option. Have you driven both the 2.5 and 3.2? if so is there a vast difference?
- tr7v8
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Re: 996 engine reliability
Err no the only Boxster I've driven is the one I boughtBrucey wrote:Hiya Jim, thanks for your reply. I must admit I have also thought of getting a 3.2 986 as this would be a more financially viable option. Have you driven both the 2.5 and 3.2? if so is there a vast difference?
Jim
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sulzeruk
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Re: 996 engine reliability
I had had a small hankering for a 996 for a while as the prices have been near rock bottom over Christmas time. A chance conversation with a guy that runs a car business from the unit round the corner from mine and I am now the owner of a 1999 C4 with a stuffed crank. In my opinion, I would rather buy a car with a blown engine and repair, that way, I know exactly what has been done and can put right all the bits that go wrong. I have spoken with a fare few folk about the IMS issues but in the end went for a Hartech replacement bearing. The cases are also getting the Hartech re-rounding treatment with the top rings. The bores on the car looked very good and also the pistons and rings seem to be still serviceable but I will be checking them all anyway. I had to get a replacement crank from Porschapart (came out of a 2.7 Boster!) and have bought all the other parts from my OPC who gave me a generous discount. I have went to town on new parts so pretty much any parts that can have problems will be changed,also any plastic part as well due to them going brittle over time, things like the AOS and the oil pick ups in the sump. All chains, ramps and tensioners will be changed as well as every seal and O ring. The car had had a new DMF and clutch in the last 15,000 miles so they are still in good nick. I would think it will cost me £4,500 for all the engine work and will be building it myself. So a pretty cheap 911 at the end of the day.
Alasdair
Alasdair
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Re: 996 engine reliability
Alasdair, this is the philosophy I'm using with mine. I'll run it for a while & then drop the box & replace IMS & RMS. The RMS tool that Porsche use looks simple enough to knock up on the lathe so as there was a good picture of it in last years Porsche mag called Excellence that'll be the way I go. I may import the LN Engineering IMS fix from the US.
Jim
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sulzeruk
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Re: 996 engine reliability
Hi Jim, I know at the end of the day that the engine should be as good as new, the gearbox was rebuilt about 18 months ago as well so that is anothe thing not to worry about. The rest of the car looks OK apart from the 2 silencers (usual pproblem of rotten seams) and the front bumper is stonechipped to death. Easy fixes!
Alasdair
Alasdair