Yikes, almost 268k...

With all this discussion on IMS replacement, and discussion about when one might replace thier IMS bearing, I am wondering how many miles you have on your current IMS bearing and if you have any plans to replace:

1. Boxster year and mileage? 2002 base tip - 165K

2. Miles on current IMS bearing? 126K Not thinking about replacing

3. IMS ever replaced and Mileage when replaced (if appliable)? Yes 39K

I was already doing the clutch. Old bearing had a very small amount of play. I tend to drive fairly hard in general.

However, I do suspect that my chain tensioner/guides need to be replaced… occasionally, during the initial start-up only, and on cooler days (35-55F), the rear end of car sounds like metallic marbles in a tumbler for a split second… then settles down nicely, and, as I said during the initial start-up only.

Perhaps, could it be the starter/flywheel gears stripping at engagement… or even the catalytic heat shield? I've not been able to detect anything loose underneath to give off that kind of noise/vibration.

Daily driver 8-9 months of the year, using M1, 0W-40, 5-7K change intervals… "clean-of-visible metal" oil filters after removal.

Any ideas, comments or suggestions are certainly welcomed... and most appreciated ;-)

'01 boxster s, biarritz white/metropol blue, 123,456 smiles...

Quote
FrankZ, Chicago
However, I do suspect that my chain tensioner/guides need to be replaced… occasionally, during the initial start-up only, and on cooler days (35-55F), the rear end of car sounds like metallic marbles in a tumbler for a split second… then settles down nicely, and, as I said during the initial start-up only.

Perhaps, could it be the starter/flywheel gears stripping at engagement… or even the catalytic heat shield? I've not been able to detect anything loose underneath to give off that kind of noise/vibration.

Daily driver 8-9 months of the year, using M1, 0W-40, 5-7K change intervals… "clean-of-visible metal" oil filters after removal.

Any ideas, comments or suggestions are certainly welcomed... and most appreciated ;-)

These engines are inherently noisy on startup and after sitting in 35F to 55F temps after having been run this just makes the engine sound more noisy as the cooler engine/car transmits noise better. What you are hearing is probably the cam chains rubbing against the tensioner rails for a moment, half a moment, until the oil pressure builds to take up the slack. The most likely chains are the ones furtherest away from the oil pump which is the length of chain between the exhaust and intake cam shafts.

My 02 Boxster had to have its VarioCam solenoid and actuator replaced at around 225K miles and while the solenoid was bad, as was the actuator (internally -- it is a sealed aluminum housing containing hydraulic valve or valves), the plastic covered chain rails showed little wear. So little the tech said there was no reason to open up the other side and replace the actuator with its pair of rails for the sake of preventative maintenance.

A higher pitched noise is probably a buzzing heat shield or even a converter brick loose in the converter housing. In the case of the latter though this is often accompanied by a CEL with an error code that points to the converter but not all the time.

Marc, thanks so much for the reply...

What symptoms were experienced with your problematic VarioCam solenoid and actuator; were the components easily accessible, or did the procedure require engine removal?

This disturbing, rapid, staccato-type, brief chatter really sources like a momentary slack in a chain which buzzes over another surface… then, as you mentioned, is quickly and totally dismissed as the oil pressure builds. It might be difficult (intermittent) to duplicate for an independent or dealer to check out.

What might be the consequence (and fix) for the chain and guide 'wear' continuing this way? This has occurred perhaps a dozen times during the past couple years now… with increasing regularity when cool temps.

Would I eventually expect to see bits of metal or plastic in my drained oil pan or old oil filter?

I don't really think it's the cats, but could be... and have not experienced CEL, yet.

Quote
FrankZ, Chicago
Marc, thanks so much for the reply...

What symptoms were experienced with your problematic VarioCam solenoid and actuator; were the components easily accessible, or did the procedure require engine removal?

This disturbing, rapid, staccato-type, brief chatter really sources like a momentary slack in a chain which buzzes over another surface… then, as you mentioned, is quickly and totally dismissed as the oil pressure builds. It might be difficult (intermittent) to duplicate for an independent or dealer to check out.

What might be the consequence (and fix) for the chain and guide 'wear' continuing this way? This has occurred perhaps a dozen times during the past couple years now… with increasing regularity when cool temps.

Would I eventually expect to see bits of metal or plastic in my drained oil pan or old oil filter?

I don't really think it's the cats, but could be... and have not experienced CEL, yet.

something I posted on this when it happened about 2 years back.

After a 30 minute uneventful drive from home to the office the engine developed an odd idle condition upon pulling into the parking lot at the office.

One moment the engine idling at normal idle speed then it drops to around 500 rpms (by the tach dial/needle) then almost no sooner does it reach 500 that it climbs again to the normal idle rpm and this cycling repeats over and over again, at least for the few minutes I let the engine idle.

Gave the engine some throttle and it ran and sounded ok. No other symptoms, Oh, CEL was not on.

Plenty of gas [in the gas tank].

Hooked up the OBDII reader and no current DTCs. No CEL so I didn't expect a current DTC.

Checked for pending DTCs. There is one. P1341: 174 Camshaft Adjustment, Bank 1 - Signal Implausible, 174 Camshaft Adjustment, Bank 1 - Below Limit, 174 Camshaft Adjustment, Bank 1 - Above Limit.

Used reader to clear DTCs (including pending one). Symptom not much changed.

Might add I drove the car home taking it easy but not too easy to avoid working the VarioCam any more than necessary.

The engine did not have to come out of the car.

To get to the solenoid requires the camshaft cover come off and once off the cams have to be secured and so on. The job takes some time. I do not recall the number of hours now but I'm pretty sure is more than 4 and that's probably a low number now that I think about probably closer to 6 or more.

The actuator was found to be bad and it was placed too.

These engines will drag chains upon cold start. As long as the noise isn't too severe or lasts too long or appears at other times (hot idle when oil pressure lowest) or you hear what would be the chain slapping the rail and the oil filter housing oil and filter remain free of any composite plastic and aluminum debris the noise you describe is probably nothing to worry about.

The noise should be easy to reproduce. Drive the car around until it is good and hot. Take the car to the dealer or indy shop and park it and let it cool overnight. Upon the next day's first engine start the noise should be present. The tech at that time can advise you. I would frankly be surprised if it is deemed anything to worry about.

But get a 2nd opinion. Won't hurt my feelings.

The chain rail composite plastic is probably not wearing. It is tough stuff and designed for that application. Engine makers have been using this stuff for years with good results. My 01 Datsun 510 engine with its SOHC and long (and I mean long) cam chain ran against several rails/tensioners and the covering wasn't fazed.

If it was wearing you be finding bits of it in the oil filter housing oil and in the filter. Once enough has come off then the chain runs against the alum. rail and the oil will develop a metallic sheen in short order as the alum. particles are concentrated in the oil filter housing oil.

My 02 Boxster now has over 267882 miles (as of earlier today when I filled up the gas tank and wrote down the mileage). While the one actuator was bad its cam chain guides (which are used to push against the run of chain to adjust timing of the intake camshaft) showed no real signs of wear. The chain side plates do wear into the plastic but only as deep as it takes for the rollers to make contact with the plastic. From then on the chain doesn't drag but rolls/slides along the rail.

None of the other cam tensioner rails have needed any attention at all. Not even the other actuator. I asked the tech about replacing it at the same time he replaced the bad one and he said if the bad one showed signs of exceptional wear he'd possibly recommend replacing the other side but the bad one showed no such signs of any wear and he advised me to leave the other side alone.

Really I think your car's ok. But like I advised above get a professional tech's opinion.

and Pedro's 234k. We've got some catchin' up to do here, eh?

Once again, Marc, thanks for the 'sound' advice (pun) on getting my tech's opinion. Oh, and of course, during these last few warmer days here in the Midwest, my '01S has been starting v e r y normally. Sweet permagrin revisited… a good thing!

So, during my next indy visitation, I shall see what he thinks unless other anomalies catch my attention… or the sky falls.

Time to enjoy the ride… and support OPEC!

Oh, BTW, good grief, just paid $4.79/gal yesterday for 93 octane, some 50 miles west of Chicago (and higher in the city).



'01 boxster s, biarritz white/metropol blue, 123,456 smiles...

cars with lots of miles achieve lots of miles. Ok, that's trite., but below the data is the fact that these cars only got those miles one way - being driven regularly. A car driven a lot goes significant distances - so most of its mileage is with a warm motor - good. The oil gets > boiling for both water, fuel and other contaminants - good. It gets lots of splashing if its revved a bit - good. It doesn't go weeks during which oil leaves the bearings - good.

For babied and garage queen cars, invert that. In fact its a concern of mine with 3 cars that i drive. I make an effort to take each one out for a good long drive ~ 1/wk or 10 days, hopefully meaning 40-60 minutes. Good for the motor, the battery and the soul.

Of course this is not controlled nor statistically significant.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

What bearing did you replace the original with would also be an interesting question to ask.

2002 Base approx. 74K No issues.
May replace upon clutch job, but have extended Warranty on car....so, not sure if I will bother or not.

2001 S, 6 Speed, 73K

Original IMS. Flange was replaced during RMS fix under warranty at about 25K.

Will inspect and likely replace when RMS or clutch need to be done. Maybe next winter but not sure yet.

1999 - 118k daily driver - no IMS issues

Yes, my IMS failed, causing total engine failure 2 months after 4 year warranty, in 2006. Porsche replaced engine under goodwill, and was told the IMS was an "upgraded" version, whatever that means. LN was not available that I know of at the time.

I still love driving my boxter as well as the day I drove it out of the showroom floor in 2002, and after the failure, I was determined that I would drive it daily and put as many miles on it as I could.

Judging from the date and description, you probably got the 3rd iteration of the IMS, the one that seems best so far but gets expensive if you do have problems.

The LN web site at [www.imsretrofit.com] is where I'd start

ok means not dying, btu not perfect either.

below "good".

Both cars used regularly, car #1 hard (track too)

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

Barry,

1. Per mikefocke's point - what bearing did you (and others) use for replacement?

2. Barry, you replaced at 39k, now have 165k on a 2002. It would seem then that you did the replacement quite a awhile ago. Probably before LN's came out, or even before many of us knew that there were improved bearings on the market. So, really curious about what you used.

Bob

At 30,488 the dealer replaced a RMS and also installed: 996-105-017-02 Shaft base.

Currently I have 91,000 miles on a 2002S

2001 S, probably single row, still original, 105,000 miles. Plan to swap when clutch is replaced - probably in the next 5000 miles. Will probably use IMS Solution or LN Retrofit. Still undecided.

... I decided to drop the tranny to look at my clutch.
It still had some "meat" left, but I decided to drop a new one.
At the same time I put in a new dual mass flywheel (damaged from a lengthy RMS leak), a new Rear Main Seal and a new Ceramic Ball IMS Bearing.
My original bearing as still pretty good though.
Now at 234,000 miles I will again drop the tranny and install the TechnoFix DOF so that I'll never again think about the bearing.
Happy Porscheing,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

The IMS was not touched then?

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

Yes, I did, but that was after 203,000 miles.
It was at 213,000 when I starved the engine for oil at the track and had to purchase a new (used) engine and rebuild it.
BTW I reused the ceramic ball bearing IMSB on the rebuilt engine, so I add back the 10,000 miles.

Since that time I've been working on ways to solve these issues and will be bringing several new and exciting products to all enthusiasts, such as:
TechnoSump - Deep Sump Kit
TechnoPulley - 15% underdrive pulley
TechnoFix - IMS bearind Direct Oil Feed solution

and a few other products for the track such as:
TechnoDuct - for added front brake cooling
TechNACA - NACA duct for miscellaneous placing

Happy Boxstering,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

The IMS in my car failed at about 65,000 miles, and the engine was rebuilt, with the new Porsche IMS. Car runs great.....

I won't proactively replace. My plan is to drive my car until it crumbles or blows up, then buy a used 2013/2014 Boxster S, some medium blue, black leather, as few options as possible. Hoping for this in about 18 months...

You aren't looking for your car to blow up in 18 months, are you? Anyway, I just went through the process of buying a late model used Boxster myself. You will find most are in the hands of dealers, so you will probably be looking at paying the dealer markup and not be quite sure of what you are getting. Specifically, if you search Autotrader now for a Boxster with manual transmission model year 2009 or later for $45K or less for sale by private party, you will find exactly 3 in the entire country. There used to be 4, but one of those was the one I bought. One of the ways a dealer can give an unreasonable discount on a new Boxster, a discount that would raise eyebrows, is to give an unreasonably high trade in value on a trade. I'm not saying that this is the current situation but you won't find out unless you investigate.

you can't be sure of what you're getting, but at least with the dealer there can be a warranty. Even if they don't actually do the entire used certfication checklist, they would still be responsible for everything on it.

no I'm not hoping that it blows up in 18 mos, I'm hoping to start the gently used car search around then. I expect it'll be a tough, slow search for a barebones, manual S, but hope that my current baby will continue to treat me well until the search is complete. Thanks for sharing thoughts from your search.

I do worry a little about the one in the 01 that my friend now owns.

I had 50k miles, my bearing had little to no play. I think that any play is bad and an indication that the bearing is beginning to fail. I worry about the indies doing the work as I feel, new problems were created in my thorough servicing.