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YOUR RESEARCH996 with M97 engine - Surprise!
Reported or suspected cause
swap was not a porsche sanctioned swap
Reported cause
No successful repair reported for this finding.
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4) Well, one problem is the swap was not a Porsche sanctioned swap.
Leading evidence: 'swap was not a porsche sanctioned swap' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'swap was not a porsche sanctioned swap' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Check once i get the serial number' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Performed · outcome unconfirmed · Original poster
First question I asked before buying was - "Has the IMS Bearing been replaced?" Answer was "No."
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Performed · outcome unconfirmed · Original poster
While they were in there they checked and replaced the engine mounts, and the drive belt.
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Suspected cause
That said, it�s probably a 996 engine with the larger bearing.
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Suggestion
I am in the process of replacing my blown 2000 996 engine with a 997S engine for big bucks...Consider yourself lucky you got it for free :-) Even though I had an LN IMS in my 996 engine, I lost the engine to oil starvation and lost a crank bearing.
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About seven months ago I purchased a 2004 996 C4S (Manual transmission) with about 45k miles on it. Car is in FANTASTIC condition seemingly inside and out. I have had a couple of minor issues (sensors going bad) but what do you expect from a 14 year old car? Before I purchased the car I looked at the history of the vehicle. Biggest thing recorded was a clutch replacement at about 35k miles. Test drive went very well. I was shopping with a dealer I trust. (Used car dealership specializing in Porsche, BMW, Mercedes, Lexus - well respected and we are friends of the owners daughter and son-in-law).
First question I asked before buying was - "Has the IMS Bearing been replaced?" Answer was "No."
Ok so I buy the car, save up some cash and pay for the IMS Bearing replacement (and clutch while you are in there - might as well). I turned the car in last Tuesday. Thursday I get a call from the dealer and he says that the work was being done, they removed the engine to do the replacement and lo and behold there is no need for the IMS Bearing change. In fact, they look at the serial number of the engine and it turns out it is a Porsche 997 engine (Says 06-08 on the work invoice) in the vehicle.
So I am a bit confused. There is no record of this work being done. Ever. The dealer was completely unaware until they went to do the IMS Bearing replacement. While they were in there they checked and replaced the engine mounts, and the drive belt. The clutch is in perfect condition (as I kind of expected) so they didn't do that replacement after checking with me. They are providing me the serial number of the engine tomorrow. They literally charged me for the work "at cost". So the dealer made no money on the work they just did.
This leaves me with some questions:
Why was this done? Is there any way for me to find out? I suspect maybe a failed IMS Bearing or something else bad happened to the 996 engine and it was then swapped out.
Why was there no record of this work?
What does this do the resale value of the car? The 997
Mezger
engine is widely considered to be a superior engine (?), but it isn't the original engine.
Are there any consequences to this kind of swap? Anyone familiar with potential problems meshing the two?
Thoughts?
Previous owner might of replaced it out of pocket. Maybe a money shift. If PCNA didn't replace it and if there was no warranty claim it wouldn't show up in a CarFax. The dealer could tell you how many hours are on the engine.
BTW, not a Mezger. Mezger reserved for the GT3 and Turbo. The 997.1 (M97) engine is similar to the 996 (M96) but with a beefier, but non-replaceable, bearing. Much lower chance of IMS failure but it's not zero.
Thanks user 996AE above corrected me on that part - I was working under a mistaken thought that all 997s were Mezgers. Now I feel dumb for trying to sound smarter than I am :P
No worries.
Like others have said the 06-08 M97 engines are solid and overall better than the 996. While not a serviceable IMSB they are more robust, and you have more HP, Torque etc...
1-2% chance of IMSB failure? Not an expert but from what Ive read its pretty darn low.
VIN on engine may help you source it. Was it knew, rebuilt, from a salvaged 997? Service history?
Keep up posted. This is interesting.
Thanks for your help (and education). This is my first Porsche and while I did quite a bit of research in advance there is no way for a non-car person like myself to learn it all at once!
I'm getting the serial number tomorrow. Looking at the invoice it notes '06-'08 engine. But I will check once I get the serial number. Where WOULD I check? (if you know)
I'd have to see the engine serial number to possibly work out if the engine is truly a 997 engine.
My understanding is Porsche would not install a 997 engine in a car that came from the factory with a 996 engine.
I believe you are in the bay area? If so has the car been smog checked? It should have been before it was sold. It is the seller's responsibility to get the car through a smog check and that it pass.
As for your questions:
1) Who knows? Only the previous owner maybe unless he just had the car in and the engine got installed. Might surprise some here but some owners are pretty nonchalant about things like this. (And a few would have kittens...) If you can find out where the work was done you might learn why it was done. You might be able to deduce where the work was done by referring to a CarFax report. This report can list when and where the car was in for various things and this engine replacement might show up.
At least the CarFax report can (or may) show where the car spent some time and you can call various dealers in the area and with the VIN see if there is any record of the car being worked on. I did this when I was researching my 2003 996 Turbo. Avoid asking about previous owners. Focus on what work was done to the car. Maybe you'll end up talking to the place that did the engine swap.
For 2) There is a record somewhere, unless the shop that did the work discards invoices after so many years. Dealers do. Well, not discard but remove/file. My recollection is Porsche dealers only keep on file something like 4 years back at least on the dealer computer system. Parts department only keeps records for 2 years. I do not believe dealers destroy records but the paper ones get filed and stored and often times off site and are not really accessible to just run of the mill queries. If (big if) the engine swap was done under warranty of some kind the factory may have a record of this. Senior techs at dealers can access this database.
3) You just got the car and already you are worrying about resale value? Really at this time it is hard to say what if anything this engine replacement does to the resale value since it is not clear just yet which engine is in the car.
4) Well, one problem is the swap was not a Porsche sanctioned swap. IOWs, the car is a Frankenstein, so to speak. But before you lose any sleep on this subject wait and see if you can figure out if the car received a 996 engine or a 997 engine. It may just be the car is less a Frankenstein and more a "Six Million Dollar" car. "... Better than it was before. Better...stronger...faster ."
I am in the process of replacing my blown 2000 996 engine with a 997S engine for big bucks...Consider yourself lucky you got it for free :-) Even though I had an LN IMS in my 996 engine, I lost the engine to oil starvation and lost a crank bearing. So you can lose engines for other reasons too. I would enjoy the extra power and just hope it was all done right. Cheers.
I am betting this is what you are dealing with. I purchased a salvaged 911 for the motor when I blew my motor on the track. I really lucked out that it had one of the replacement engines built after 2005 with the 997 bearing.
Also had a bunch of other 997 parts on it, like oil baffle and swirl pots, etc.
Replacement engines that are seen as an improvement and done well (like this one appears to be) wouldn�t hurt value, but instead, retain value. That said, it�s probably a 996 engine with the larger bearing.
CVTuttle,
I had a similar experience that I described before. Essentially, was planning to have IMS done after purchase, but in the process of calling around to flesh out dealer service history, found out that it had a new M96 engine due to IMS failure. It was listed as "inspection" on Carfax. The only way I found it was to call all dealers on the Carfax. Fortunately I found a nice service rep who noticed this, told me and sent me the invoice for my records. Hopefully you'll find a similarly helpful person if you call around.
It now has a high serial number "AT" engine with the non-serviceable IMSB with a much lower failure rate. I see it as a plus from a value standpoint, as I have a more reliable engine with ~20K miles with a garage queen body with 40K miles.
I also have a 2007 M97 engine in my 996, but it does not give me full power, experts have said I have to replace with the original 3.4L m96 engine.
Any suggestions would be helpful on how to obtain full power and acceleration.
My email is terje.gronlie at gmail.com
You'll need an aftermarket tune. No need to install a 3.4.
Variocam operation is different between the two engines. Not sure if you'd be able to get that operational with your existing ECU
I bought a 997 ECU, part number 997.618.601.03, will this fit in the M96 harness or do I need a M97 harness and rewire? If it fits, can it be reprogrammed/mapped so the car will run better?
https://www.stuttcars.com/porsche-91...ers-all-years/
997 COUPE S/CABRIO S M97.01 2007 7
687 00501
>40000 6ZYL 3.8L 261 KW 350 hp
Is this the correct engine?
Mine reads: M97/01
68715829
Honestly, I'm surprised it works at all. It would seem if you're using the original DME that is designed for the M96.01 3.4L Variocam VVT 5-chain engine, putting a M97.01 3-chain Variocam Plus would run horribly, if at all. I could see swapping out apple for apples like a M96.05 in place of a M96.03, but this is like apples to grape fruit. As mentioned, your best bet is to see if the DME can be tuned or a new DME programmed that would better match the M97.01 engine. That being said, I think the advice from your "experts" is spot on, the best course of action would be another 5-chain 3.4L M96.01. If this M97 engine has a clean bill of health, I'm pretty sure you'd have little trouble trading it for a proper M96 because of demand for M97 engines at the moment.. Just my opinion.
Post a pic of the dme (computer) on the rear shelf. It may have be swapped already. There isnt a lot of changes in the wiring between a 3.4 and a 3.6/8. Although your car was a cable throttle originally so some wires must have been swapped or added.
Its an interesting swap. There a few ways to do it. U can use a 996 3.6l dme (with tune), harness(or mod existing) with a matching immobilizer and swap the key fob. This is basically what i did with my mezger swap.
Other way would be for ecudoctors to disable the imobilizer so it doesnt depend in the dme or key and then use the original dme (probably with some tune mods) and custom wiring.
If u can pull the drivers seat i wonder what it has for the immobilizer.
Seems you have everything running/starting normally, no engine lights on ?, with a good AFR, but
"does not give me full power".
Sounds like your incorrect current dme/wiring/gauge cluster/whateva/etc, can't/isn't controlling your variable valve timing or variable valve lift. So
valves are only half open
and cam timing is retarded. = NO Porsche POWER
You could go old school like many other engine performance builders do. Lock in the cam timing with sprocket advance,,, and see if you can jump out the valve lift solenoid for full lift all the time. This would give full high rpm power back with maybe a small loss in midrange throttle response.
Might get a lumpy idle or not, if so, a compromise in cam timing could smooth it out.
I Never did this on a m96 engine, but have done exactly this on other engines very successfully....
jmo
Not sure who could or would do this in your area. If explained correctly too a well knowledged 997 tech, they could probably figure it out without much problem. but it would take the right tech...
Did you do the engine install yourself..? If so you are familiar with the engine and its functions/connections. And could probably do it yourself..?
I'm not familiar with the exact cam controls of the 997 engine. But assume cam advance and valve lift control is done electro-hydralicly with solenoids.
If so it might be as simple as energizing the cam lift/advance solenoids constantly since the 996 dme can't control the 997 cams but you could...
I don't believe constant high valve lift would be a problem, as racers usually do away with the oem varible lift lifters and use full lift all the time.
On cam timing, full advance might be to much for great low rpm, maybe, maybe not, have to try it and see how response and drive-ability is. Could always keep solenoids in constant advance mode and back off the cam gear till you get a good compromise on great drivability/throttle response.
Or you could do whats really needed and change DME and wire harness and whatever else is needed to control the 997 engine in a 996...
jmo
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