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YOUR RESEARCHPoll about IMS and your car...........
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Reported cause
Bought my 2000 Boxster in 2003 before the issue was diagnosed.
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Reported cause
The IMS in my car was already replaced w/a dual row LN retrofit kit but the warranty is due to expire next year.
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Performed · outcome unconfirmed
Bought perfect condition low mileage 03 and installed Solution
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Performed · outcome unconfirmed
Then drove it for a month with weekly trips from OH to MI, and had LN retro installed when time permitted (4k miles later).
Replace (as i have heard carfax isn't always clear
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Performed · outcome unconfirmed
No mention of the IMS being replaced (as I have heard Carfax isn't always clear on details),
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Suggestion
I knew about the potential IMSB problem (2002, Tiptronic, dealer purchase - no records) got the regular PPI which revealed that the trans had been replaced (could tell by the serial number).
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49 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
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Bought sight unseen from a dealer with 23k miles, took a rental from OH to TN, drove it 500+ miles back the following morning. Then drove it for a month with weekly trips from OH to MI, and had LN retro installed when time permitted (4k miles later).
Bought perfect condition low mileage 03 and installed Solution
Bought '01 driver, rode it hard, and sold it for a profit with original
Bought '99 with p.o. replaced unit - included original in sale that was absolutely perfect
I did all the PPI checks I could short of dropping the transmission thinking the bearing was stock. One of the more valuable readings was the cam deviation which was -0.42 and 0.50 telling me that things are in spec. Drove the car for 1500 miles and to my surprise found out by flipping through the Porsche manual and maintenance that the IMS retrofit was done 10 years ago and about 50k miles. I'll be scheduling to have the work done sometime this winter with probably new clutch due to time in service.
Knew about it; gambled and lost; now driving an LN 3.8 litre with the Solution. An 03 with 70K on the clock and 30K on the engine. It sounds like it might be worth a few bucks. Hmmm.
I knew about the potential IMSB problem (2002, Tiptronic, dealer purchase - no records) got the regular PPI which revealed that the trans had been replaced (could tell by the serial number). So that created our "hope" that they had also replaced the IMSB at that time. The car was in excellent condition which suggested the PO would have been diligent on maintenance and thus possibly replaced the IMSB.
That is the kicker isn't it? You come to the forums and you see IMS this, IMS that but over the last few years its the bore scoring that has been rearing its ugly head. I bought mine two years ago and if I knew what I know now I might have considered otherwise. IMS is a relatively easy fix and its really not that bad price wise considering these are 911s. With bore scoring you have no choice in the mode of fixing, either an expensive engine replacement that will be prone to the same potential problems or an even more expensive build that will at least never have those problems.
Check out the Focus on Bore Scoring videos. My personal take is that it's looking to be a bigger problem than the IMS and a lot more costly if you have it. Things I'm doing to hopefully prevent it or limit the chance of it happening:
- Do not idle the car to warm it up. Get in and go keeping the revs under 3k till operating temps are reached
- Use good oil and change every 5k or 6 months. I'm using DT40. Motul Xcess is also a good option.
- Use good gas and keep your injectors clean
I don't think you can truly prevent it 100% unless you rebuild the motor with Nikasil sleeves. Only way to know if you have this issue is a bore scope, ideally from the bottom. If you can hear piston slap, then it's probably pretty bad already. Look for soot on the driver side exhaust as bank 2 is most affected by this.
2000 C4 Cab 6MT.
Knew about it, (saw the work order/receipt for the double row IMS replacement not the "Solution") and bought it just over a year ago w/o a PPI.
No regrets yet.
2002 C2 Tip -109k miles when I bought it - PO to the PO had the IMS Solution installed. PO had a valve guide crack and the complete engine rebuilt with nikasil liners. Engine had about 108k miles on it when it was rebuilt.
When I bought my car it had 2 IMSR stickers in the door jam. After about 3 years I decided to do The Solution (because I was changing out the cam chains & pads - in addition to a bunch of other "while you're in there" stuff). About a year and a half after doing all the top end/ancillary work it developed a nasty tick/tap/clack so I decided to have FSI do a proper rebuild for me (Stage II track performer - 3.4> 3.8l). The upshot was that they discounted the cost of the Solution - since they were able to just re-use it for the rebuild...
2001 owned since new, since I sometimes travel to remote areas, I replaced the bearing just for insurance. Apparently it bears repeating, this 'problem' is waaaay oversold; if not, it's waay over-worried about.
i think the math is pretty simple, spend $2k to protect a $30k car from instantly being worth $5k. If the failure rate is 8%, .08x25k = $2k so the repair cost is fairly priced.
As the care-taker of a 1999 model, getting up close and personal with the ins and outs of the bearing isn't necessary, but as somebody that's always looking for something else, it's been my understanding that this is a $5,000 fix rather than $2,000. Seems that the bearing, RMS, and clutch are a triad that should be done altogether; maybe that's where my number came from? Would you guys that have had the work done comment on cost, and whether you did all three, and is there something else that should be done as well?
Yes !! The AOS/UAOS !! Most people in the know usually replace the AOS at the same time. It has a notorious reputation for failing, most survive the failure with just rough running, CEL, or smoking that leads to the diagnosis, buy many fail from sudden Hydrolock that is catastrophic and is sometimes not properly diagnosed. The engine is destroyed with cracked cylinders, bent or broken rods and no "bread crumbs" that lead back to the root cause (like in the case of IMSB failure), just an oily mess or broken parts.
The IMSB failure have been over-publicized, the AOS failures have been under-publicized.
We have had 4 known cases here on Rennlist (catastrophic) just this year.... and quite a few close calls/ "dodged bullets"..
My post from the stickied IMS thread;
11/99 build date, service performed 08/2017 with 26,800 miles. Indy ran by Jeff Brubaker of Kraftwerks in north central OH, found on LN's site as a certified solution installer;
Replaced stock dual row with LN retrofit (pending passing pre-qualification checks), replace RMS, AOS, clutch, flywheel, fluids, LN magnetic drain plug, scan service/activate PCM, and install LN spin-on filter adapter.
Total with tax; $3,373.90
I've thought the same thing. There are several ways you can look at this. I play blackjack on and off and I relate this to the concept of expected value (EV) in advantage play gambling. So, like the math above says a fix for this has an EV of $2K if you accept that it's an 8% failure rate and the failure will cost you $25K. Anything more and it's "not worth it". Other people think about it like insurance. They want the piece of mind and can't fade a $25K loss so they're willing to pay more for a fix. There are lots of other factors (your time, loss of the car) but the $2K figure above is a great starting point for how much a fix is worth to you.
Bought my 2000 Boxster in 2003 before the issue was diagnosed. Loved the car as I still do. When I became aware of Jake Raby's M96 engine rebuild class in 2008 I went to the 1st class.
When i got back home I pulled the engine out to send the case to LN for Nickies 3.6 cylinders install. As I was disassembling the engine I saw the IMSB was failing so I sent it also.
LN pressed in their TripleRow IMSB and I have no plans to change it. Engine has about 70,000 miles on it since rebuild.
I have a extra 2001 engine I rebuilt the same way with the Triple row IMSB.
So, true!
Based on my reading since I bought my 2000 C4 Cab a year ago, there are at least 3 failures that can occur that can destroy a 3.4L 996 engine:
1) IMS
2) AOS
3) Timing Chain
The question is how "likely" any of these failures are going to happen to you and NO ONE knows. I prefer to take @
ssherman68 "expected value" approach to the issue.
The IMS in my car was already replaced w/a dual row LN retrofit kit but the warranty is due to expire next year. Some here suggest that replacement of an LN Retrofit w/the LN Solution is "mandatory" or at least highly recommended.
I personally disagree with this "advice."
If LN's retrofit kit is so fragile, why replace the OEM IMS bearing in the 1st place, if there was no evidence of any problem w/it to begin with given than less than 10% of 3.4L engines have been found to have the problem and most of them (that had the problem) "blew up" well before the 87k miles and 16 year when the LN Retrofit kit was installed in my car?
The way I see it, if the OEM IMS bearing in my car didn't fail after 16 years and 87k miles, the LN Retrofit should be good at least as long, if it's any where near as good or better than the OEM part. I may be wrong in making this assumption but I'll willing to take the risk (at least until, as noted below, I sell or trade the car away).
As for the AOS and timing chain, I would probably install the UAOS if the engine pressure in my 3.4L engine rises above 5 in/H20 which is NOT the case yet but I'll certainly keep an eye on it.
As mentioned above, the AOS "problem" exists but is not well know or discussed outside of Porsche speciality sites. I do note HOWEVER that it is mentioned above that ONLY 4 members here have reported the problem causing their engines to blow up, which (to me) is not a significant # given the many 996 owners (hundreds if not thousands) who make use of his site.
That doesn't mean that it is not a potential problem but, again, it's only a problem "if it happens to you."
Lastly, the timing chain. I'm also not sure how great a problem this is but I have read several reports on it happening to owners here. This is DEFINITELY not a part that I would bother to replace there are obvious signs of the problem (notably engine misfires and rattling noises). In this case, I'm just willing to roll that dice and take the risk the the timing chain will not fail because the cost of removing the engine and splitting the case would just not be economic. Better to rebuild the entire engine in that case.
Anyway, this is how I process all of the "doom & gloom" expressed about the IMS, AOS and other problems that COULD affect our 3.4L engine and personally I have already decided to sell my car or trade it in for a 996TT just to be done w/it.
I'm just not all THAT worried that my car is going to blow up before I do that but, if it does, I'll just deal w/it .
In the meantime, I'm just not going to worry about it anymore!
As the OP, my apologies for seeming to toss water on humping dogs just to watch the squirming, but I wanted to learn if there's a way to sense something about to happen. Since my question, I've learned that there isn't a perfect way to do this, so roll the dice at purchase, and add $3500 worth of improvements right off the bat, and then drive with a grin...
My next OP will be about the AOS R&R, but that's a different thread.
'bama I think it really comes down to your own personal risk tolerance and assessment. There are options for a M96 engine ranging from $0 - $40,000+ depending on how far you want to take it. None of them are guarantees for life. When I bought my car I was also a Nervous Nellie until I finally came to the realization that there's nothing I can do to prevent bad things from happening, ultimately. So I could either keep throwing money at the car or just enjoy the sports car I bought and take the hits as they come. On the flip side of that coin I think an ounce of prevention can cure a pound of heartache for things like the IMS which can and most often do fail "out of nowhere." Things like bore scoring we can see and assess. At the end of the day you need to find your own balance of prevention and cost that helps you keep your toes tickling the carpet of your 996 and be able to drive the thing the way it was meant to be driven. Even though "buy a Camry" is a snarky-assed comment, there is some truth to it if you just spent $20-30k on a sports car and drive it like a Camry. To me that's money just absolutely wasted regardless of the costs afterwards.
Well-said, Doc. As a guy that care-takes not only a 911, but also a Jaguar and a diesel motor home, I'm used to some eye-popping repair tickets from time to time. Not fun, but worth it for all the time that they're being used as they should. If I can learn what to replace before it's time, I do it just to feel better about things.
IMO, the worst feeling is having to park one of those guys on the side on the road and have the F150 crowd hoot and hollar while they're driving by, lol. I flipped a chain on my '73 S at the busiest crossroads in town and had to have several of them push the car to the curb. That was 30 years ago and the memory stills stings
That's what I'm talking about !!
Nice video, when I first looked at it I was thinking how have I missed that video, then I looked at the post date...11/3/2020 ....LMAOO just got posted !!
....so looking on-line and several parts places have them all the way from $54 to $135. IS there a difference, and if so, what has worked fine and what is junk or doesn't work right?
If you are asking about the AOS, only get an OE Porsche AOS. Others are junk. You will understand exactly why when you do a DIY replacement. It is a major PITA job. At the same time, get the UAOS and install it.
No smoking, no oil drips, no consumption beyond normal, so this would be a PM item as the result of reading your all's comments.
I can't even see the AOS with the engine in place, so a DIY attempt seems to be a PITA and best left to the shop guys. The UAOS would seem to offer the most value by allowing a much simpler replacement in the future, right?
After more reading on the other thread, looks like several more benefits from the UAOS, so I'll go with that one.
Wise choice.. The UAOS is the only significant technical advancement to the M9x engines in 7-8 years, but hopefully not the last..
It will virtually eliminate the threat of Hydrolock from AOS failure, also make ownership less costly in the long run..
I disagree. URO makes some BMW parts that are considered an upgrade over the genuine BMW version and much cheaper too. I'm not saying that URO doesn't make any crappy parts, I just don't think you can make a blanket statement.
Also, the UAOS used a URO part at the time I bought mine and may still be used.
Hey there all,
Very new potential 2005 Boxster S owner here, and I have something I'd like to get your opinion on.
I realize there can be no definitive answer here, but when checking out the carfax on the Boxster, the service record shows that in 2009 at 58,000 miles:
Clutch system bled
Clutch replaced
Clutch master cylinder replaced
Transmission removed and reinstalled
No mention of the IMS being replaced (as I have heard Carfax isn't always clear on details),
but doesn't this at least hint at it being a good possibility?
Seems like the right steps in doing so anyway.
Thoughts? Thanks and looking foward to being a member of this site!
If not mentioned, I would say it wasn't replaced. Some people feel the chance of IMS issue is small enough that they choose to drive the car with the OEM never giving it second thought. This includes when having the clutch replaced.
Exactly, the URO aluminum AOS coolant line connector is obviously an upgrade to the plastic OEM Porsche AOS coolant line connector. That shows that URO doesn't just "knock-off" a factory part at a cheaper price, but looks to see if they can improve it by materials selection.
The flow regulator used in the UAOS was decided after testing 8 different brands for the same regulator. The URO was approved for the standard UAOS, and the OEM VW/Audi was selected for the UAOS-E (Elite), due to some people insist on OEM only brand.
When I was in mid-life I was very "brand loyal" and thought certain brands were head-over-heals better than other brands. But as you learn things through time you can see brands change, some highly regarded ones start to rely on reputation/presence and others with little or bad reputations start to try harder. Plus the brand trading, sharing, changing contracts, cross company buy-outs. I am no longer "brand loyal" (have been disappointed by all of them at one time or another)..but take my purchases seriously.
Like why would anyone (outside of the dealers themselves), pay $30 for an NGK spark plug in a Porsche box, rather than to pay $7 for the same NGK spark plug in an NGK box? Answer, because they trust Porsche and the brand with their $$..
I followed most of the instruction on the board and found a well documented car that had a LN retrofit in late 2017 then did a PPI with borescope. The PO only put 15k km (about 9k miles) over the span of 5 years. I drive the car hard with multiple track days and have put the same amount in just the spring-fall of 2020 (not winter driven). The car doesn't leak or burn a drop of oil. Surprisingly to me, the only mechanical part I replaced was the AOS which was still had good vacuum but I had a few smokey track days... in hindsight I would have gone with the UAOS but the turnover time to get one in Canada was probably a while. Kind of kicking myself as the new AOS did not stop the occasional smoke puff at track.
If you read these forums long enough before buying you will get scared away from 996 ownership (rightfully so in some cases). For me, despite doing the homework I think the motor is still a ticking time bomb partially because I do track the car and things like oil starvation can be a real problem.
