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Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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8 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHOil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Reported or suspected cause

control piston in the oil pump

Reported cause

No successful repair reported for this finding.

1
Identified cause
0
Suspected cause
0
Reported fixes
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that report identifying a cause
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Reported cause

The noise is caused by the control piston in the oil pump.

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Frequently discussed work

Replace however i've also learned

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

Oil was also recently changed, however I've also learned that these cars are extremely sensitive to the viscocity as well.

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Performed · outcome unconfirmed

Oil was also recently changed, however I've also learned that these cars are extremely sensitive to the viscocity as well."

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Read full discussion summary

Leading evidence: 'control piston in the oil pump' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'control piston in the oil pump' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Replace however i've also learned' (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.

Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.

Read captured replies

1 matching discussions · 8 captured posts examined · 0 partial discussions

Compare 4 other evidence results

Replace however i've also learned

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

Oil was also recently changed, however I've also learned that these cars are extremely sensitive to the viscocity as well.

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Performed · outcome unconfirmed

Oil was also recently changed, however I've also learned that these cars are extremely sensitive to the viscocity as well."

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace piston+spring

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

I replaced the piston+spring when i did my rebuild ..while you are in there.

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace spring and plunger

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

I replaced the spring and plunger when this was first posted.

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace those parts out

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

I swapped those parts out on my 2000.

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Frequently discussed actions (7)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Replace however i've also learned

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

Oil was also recently changed, however I've also learned that these cars are extremely sensitive to the viscocity as well.

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Performed · outcome unconfirmed

Oil was also recently changed, however I've also learned that these cars are extremely sensitive to the viscocity as well."

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace oil

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

cost is less than $20 and you can do it in 5 minutes when you change your oil.

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace piston+spring

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

I replaced the piston+spring when i did my rebuild ..while you are in there.

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace spring and plunger

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

I replaced the spring and plunger when this was first posted.

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Replace those parts out

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

I swapped those parts out on my 2000.

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Run about 16-17psi (hot) at idle

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

my car was running about 16-17psi (hot) at idle, which seems low to me.

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Use tapatalk

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

Sent from my SAMSUNG-SM-G900A using Tapatalk

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Suggestion

Sent from my SAMSUNG-SM-G900A using Tapatalk

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Reported and suspected causes (1)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

control piston in the oil pump

No successful repair reported for this finding.

1
Identified cause
0
Suspected cause
0
Reported fixes
Read evidence and context
Discussions that report identifying a cause
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Reported cause

The noise is caused by the control piston in the oil pump.

Oil Pressure - Changing a Piston - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Coverage and how to read this overview

Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.

8 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

  • 986Forum: 1 discussions

0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.

0 acknowledgements have no verified action link; they do not establish a repair result.

Generation: 20261027T053112Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

I found this on an oil starvation thread on the racing section and posted a comment there - but given that people don't read that as much, I am cross posting over here to get people's opinion on this "maintenance" item... Quote: Originally Posted by insite View Post another note on oil starvation: there is a piston/spring assembly inside the oil pump that varies oil pressure with temperature. when the car is cold, it's designed to increase the pressure to around 100psi. once the car warms up, it backs off to 'normal'. my car was running about 16-17psi (hot) at idle, which seems low to me. on a hunch, i ordered a new piston & spring. interestingly, the new piston has a chamfered edge whereas the original piston had a sharp edge. this leads me to believe that porsche suspected some binding of the piston assembly in some instances...... at any rate, with the new piston / spring installed, the car is now at 23psi hot. i never logged the oil pressure under load, so i have no idea what (if any) effect it has on pressure at RPM, but i certainly feel a little better. loss of oil pressure at temp is a big concern in the M96. anything that reduces the risk to that end is a win in my book. cost is less than $20 and you can do it in 5 minutes when you change your oil. FYI, part numbers are: Piston: 997.107.125.01 ($ 5.00) Spring: 996.107.127.53 ($10.00) Gasket: 996.107.123.50 ($ 2.00) End Quote So I know this is an old thread, but I was wondering about people's opinion on doing this "upgrade" or refresh on an oil pump piston, spring and gasket. Has anyone tried this? Did it help? If you haven't done it, what is the consensus on doing it? Could it hurt? Any thoughts would be appreciated. Fred

POST 2Original post

Sounds like a great proactive maintenance item. I'll do this while I'm swapping cats. (No, not those cats......)

POST 3Original post

I swapped those parts out on my 2000. There wasn't really a noticeable difference, but the buy in was under $25, so I replaced them.

POST 4Original post

Control Piston Update - Tech 1726 Technical Information Update Engine Concern - Screeching noise from the engine during the warm-up phase. Symptom: A screeching noise can be heard from the engine at around 2,000 rpm during the engine warm-up phase. In many cases, the noise is an indication that the engine or oil pump has been changed. The noise is caused by the control piston in the oil pump. If this is diagnosed as being the cause of the noise, this updated control piston must be installed in the oil pump cover. This typically only effects early 2005-2006 models. The fix includes a new control piston and seal. Professional installation and diagnosis is recommended.

POST 5Original post

Quotes source post: 458902

I wish I would have known about this before I took my Boxster S to the track. Despite an increased capacity, modified baffles, I'm pretty sure my engine cavitated on a very hot day but well within a normal rpm range. Oil was also recently changed, however I've also learned that these cars are extremely sensitive to the viscocity as well. Sent from my SAMSUNG-SM-G900A using Tapatalk

POST 6Original post

I replaced the spring and plunger when this was first posted. I don't think that the spring really loses its "strength" but its easy and cheap, so why not?

POST 7Original post

I replaced the piston+spring when i did my rebuild ..while you are in there. From Post above pkp 4911: "I wish I would have known about this before I took my Boxster S to the track. Despite an increased capacity, modified baffles, I'm pretty sure my engine cavitated on a very hot day but well within a normal rpm range. Oil was also recently changed, however I've also learned that these cars are extremely sensitive to the viscocity as well." Potentially a terminal situation for your engine !! Suggest you search " foaming ". Known issue in your situation.High detergent oils are the worst. JGDT40 probably the best solution? Also discussed many times on BitoG site. Ford diesel pickups had this issue also. Baffles/deep sump - some designs are ineffective . Needs a horizontal baffle to prevent oil "climbing" up the walls of the sump ans starving the pickup. The windows in the baffles are another feature to improve. If they don't shut when they should,they are ineffective on longer high g curves.

POST 8Original post

Appreciate the insights. I'm going to do this when I do the EPS oil lube mod for the IMS since I will be there anyway. Sent from my SAMSUNG-SM-G900A using Tapatalk

This is a source reference. Confirm exact model applicability in the original material.