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YOUR RESEARCHMaintenance While Dropping The Engine
Reported or suspected cause
bearing failure (in both metal and plastic)
Reported cause
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Reported cause · Original poster
I also heard the more prevalent issue is bearing failure (in both metal and plastic), which will cause the shaft the impeller ride on to wobble.
Leading evidence: 'bearing failure (in both metal and plastic)' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'bearing failure (in both metal and plastic)' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Check around a little' (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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Suggestion
Parts prices have been all over the place lately but you might want to check around a little.
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Suggestion
As well as have them remove the oil pan and check for debris in the pan, and scope the bores from the bottom to check for scoring.
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Suggestion
If you are looking for piece of mind, while you are replacing the spark plugs, have them scope the bores from the top to check on borescoring.
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Suggestion
As well as have them remove the oil pan and check for debris in the pan, and scope the bores from the bottom to check for scoring.
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I have started the process of getting my first Porsche this week, a 2001 C4 with 56,000 miles (more on that in another post). During a pre sale inspection, it was discovered that the IMSB is going bad. It also appears that the RMS is leaking slightly and so is the output shaft seal off the Triptronic. Soooo, while the engine and trans is out of the car, in addition to addressing those three issues, what else would be good to address while the engine is out? I want it to be quite a while before I have to drop the engine again. I have been reading up and have some ideas, but would appreciate any input from those who know.
Thanks !
If the IMSB is going bad the engine might already be toast. I hope not for your sake. I plan on dropping my engine this winter and doing the following:
Ultimate AOS
Fuel Injectors
Spark Plugs
Coil Packs
o2 sensors
IMSB
Some other things maybe.
Congrats and welcome to the 996 club!
In addition to the list that everyone gave you...
1. Take a look at the flywheel when you are looking at the clutch.
2. Replace the water pump. If the fins go, you will have a catastrophic engine problem.
3. Consider replacing any deteriorating plastic/rubber in the engine bay while you are in there as well.
4. Replace the engine air filter so it can breath fresh air and consider replacing the MAF sensor.
5. If you are looking for piece of mind, while you are replacing the spark plugs, have them scope the bores from the top to check on borescoring.
6. As well as have them remove the oil pan and check for debris in the pan, and scope the bores from the bottom to check for scoring.
7. Cut open the old oil filter and look for debris, before replacing the oil filter and oil.
8. Make sure you change the oil AT LEAST every fall and spring. More often if you are putting more miles on the car above 4k a year or if you are tracking it. Do not follow the Porsche 15k mile oil change recommendation. This is most likely what got most of the cars in trouble with bore scoring due to lack of sufficient lubrication thru old oil that had lost its qualities.
Yeah, I know it's a big list from all of us, but it's a great car, and the good news is that once it's properly serviced, you can enjoy the car with confidence.
Keep us posted.
All vac lines good inspection and replace anything even a little suspect
AOS and lines
Injectors
Water Pump
Take a look at oil fill tube - easy and cheap to replace with engine out and inexpensive
Spark Plugs
Check and replace if needed motor / trans mounts
Thanks for all the responses. The car is at a very well known and respected shop and I will be checking with them and asking them to go over your lists. The car is running great and has been very well maintained. My list just included the water pump and AOS and plugs and tubes, so I'll be adding a few items. Better safe than sorry and I don't feel like dropping the engine anytime soon. The filter was already cut open and some very light metal debris was discovered, but I highly doubt there has been any catastrophic damage done at this point, thus the immediate fix.
As for the Triptronic, to each his own. My is necessitated due to a family members disability, but I also like driving the automatic. Stop and go traffic while rowing your own sucks when trying to sip coffee in the morning
!
Some are milage/age related, but I'd consider replacing:
IMSB, RMS, AOS, H20 pump, coils, plugs, plug tubes, cam pads, rails, tensioners, Serpentine belt, belt tensioners (if needed), grease starter pawl, engine mounts, trans mount, and anything else that looks suspicious, or is a known PITA.
I have a 6spd, so I just did all of the above, as well as clutch and flywheel.
I 2nd the vote to replace the oil fill tube. Just looking at may not tell the story. While my engine was out waiting for the tranny rebuild we barely pulled on the oil fill tube and it immediately cracked. There were no signs of a crack and no vacuum leaks prior to removing the drivetrain.
While the tiptronic is out change the diff oil. You might as well drain the transmission fluid and change the filter. Refill the tranny when it is back in the car (need vacuum pump for that one).
BTW, the AOS is super easy to change when the engine is out. No need to remove the intake manifold. Get the UAOS from Skip.
I’d be very wary of buying a car where the IMSB is “going bad”. I’d want to know a lot more about how that determination was made. Are there metal bits in the filter? Where else in the engine would they be?
I will post an update as to all the findings when the shop opens everything up. It was noted on at least two previous occasions n the service paperwork that some metal was discovered in the filter during maintenance. I asked the question during purchase, so the filter was removed and cut-open for me, finding the same issue as noted before. I was not present for this, but I have some trust in who I am dealing with. So far, I am ok with how this process has unfolded. Once all is said and done, and my transaction is completed and I drive the car home, I will provide an update. I will also start a new thread detailing how things unfolded, what was done and how things turned out.
Hopefully it will be a Love Story and not a Horror Flick ! Time will tell (should be about 3-4 weeks from now).
Ok, now a question on replacement parts. In doing a little reading (lots of pictures, so I was able to get through a lot of it), I have noticed that the after market has a lot of parts for our cars.
I would like to get suggestions about the following:
Coils - Found updated BERU for $285 for 6 - Decent coils? Any other that I should consider?
Spark Plugs - Car is stock, lots of choices out there, but what plugs do you guys recommend?
Water Pump - First, plastic or metal impeller? - Second, is Pierburg OEM?
Thermostat - I don't think I'll go with the low temp, not tracking car and I live in New England. Any advantage ton use a specific brand?
AOS - Just going with what LN Engineering sells.
I have heard several different takes on the impeller issue and I am looking for anecdotal evidence one way or another.
I have heard that if the metal one comes apart, you will definitely have an issue (make sense). However, I don't think I have seen where this is a wide spread problem. Is it?
I also heard the more prevalent issue is bearing failure (in both metal and plastic), which will cause the shaft the impeller ride on to wobble. This could allow the impeller to catch part of the engine where the pump sits and a metal impeller could damage the engine block. This seems more likely, but again, I think a metal impeller would make noise if it starts to go in this manner.
A plastic one would just fail and the only way you would know would be a temp increase. And, for the plastic one, I have heard that they too come apart (more often than metal) and can also muck up some things if not caught in time.
Please let me know if any information above is incorrect and set me straight.
coil and plugs, fcpeuro has a kit with 997 coils, bosch plugs and soacrrs gor the heat shield
Wp, get the pierburg. U want plastic cause the steel can damage the block when the bearing goes
i think borge-warner is the stock oem. If u want low temp go ln-e. I had temp issues with the cheaper one.
aos, go with the uaos they sell. Search for the reasons why, but its woth every penny
I recently did plugs, coil packs and tubes and went with Beru for coils and plugs.
I don't know where you are looking for parts but I paid $201.96 for six coil packs about a year ago from RM European. Parts prices have been all over the place lately but you might want to check around a little.
You can always find deals on coils and sensors. When you find them, buy them. Same with fuel injectors. I keep them in a box and replace at various Intervals. Going thru the exercise again over the next 12 months.
Highly recommend going with the UAOS. Oem is a brittle mess. UAOS offers additional capa abilities such as drainback if you decide to track your car. Smart option.
I have gone with Oem water pumps and replace it from time to time. It's cheap and an easy replace. Can be catastrophic if you fail to replace and it shatters. Why chance it.
Kinda like the IMSB. Another no brainer. Why chance it.
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