7 captured repliesPartial discussion capture · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHWrong Coolant Cap? - Page 1 - Boxster/Cayman - PistonHeads UK
Leading reported evidence
Check level once the car was fully cold
Suggestion or failed attempt
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
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Discussions that contain suggestions
1
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Suggestion · Original poster
Following on from my car dumping its coolant the OPC advised checking the level once the car was fully cold.
Leading evidence: 'Check level once the car was fully cold' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check level once the car was fully cold' (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.
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 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
Went to check now and when I uncrewed the cap it overflowed.
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 contain suggestions
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0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
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Suggestion · Original poster
The cap can require more force to fully tighten than one might think.
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.
7 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
PistonHeads: 1 discussions
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Generation: 20261027T042512Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Hi All
Following on from my car dumping its coolant the OPC advised checking the level once the car was fully cold. I've done this and it was low, took just shy of a litre to bring it up to the max level. All seemed fine until giving it a poke in second gear and I could hear the hiss of the expansion tank in the rear. Is this just venting any excess? I attach a pic of my coolant cap and I think it might be the wrong one as there appears to be no release valve?
Any thoughts?
Hi Finestjammy, that looks like the Cayman one in the boot, the pressure cap is on expansion tank, under rear carpet covering the top of the engine.Top up the engine one with the one in your picture fitted, does not matter if its slightly over filled, as it should drain out the excess.
How much coolant did it initially loose, as it may need a full drain and bleed with Vac system
Chris
cd1957 said:
Hi Finestjammy, that looks like the Cayman one in the boot, the pressure cap is on expansion tank, under rear carpet covering the top of the engine.Top up the engine one with the one in your picture fitted, does not matter if its slightly over filled, as it should drain out the excess.
How much coolant did it initially loose, as it may need a full drain and bleed with Vac system
Chris
Thanks for that. Yes, the picture is the one that was in the boot next to the oil cap. So is it the right cap do you think for the boot one? It initially lost all its coolant, spring clip went on one of the hoses, and had to be recovered to the local OPC. They drained and bled it I believe. I topped it up right to the max line when it was stone cold. The hiss might have just been the system venting the excess I guess as you suggested. Just gave me a fright when giving it a poke in second gear and heard the hiss from the rear
James.
finestjammy said:
Hi All
Following on from my car dumping its coolant the OPC advised checking the level once the car was fully cold. I've done this and it was low, took just shy of a litre to bring it up to the max level. All seemed fine until giving it a poke in second gear and I could hear the hiss of the expansion tank in the rear. Is this just venting any excess? I attach a pic of my coolant cap and I think it might be the wrong one as there appears to be no release valve?
Any thoughts?
Post a pic of the other side, the side with the part # on it. The part # should end in 02 or 04.
The white residue is dried anti-freeze. Looks like the cap might have been leaking. The cap can require more force to fully tighten than one might think. Are you sure you screwed the cap down securely?
The actual tank cap, the one you can't see in the engine bay is known to weep coolant unless it is in perfect condition - you get what appears to be a 'mystery' leak.
Rockster said:
finestjammy said:
Hi All
Following on from my car dumping its coolant the OPC advised checking the level once the car was fully cold. I've done this and it was low, took just shy of a litre to bring it up to the max level. All seemed fine until giving it a poke in second gear and I could hear the hiss of the expansion tank in the rear. Is this just venting any excess? I attach a pic of my coolant cap and I think it might be the wrong one as there appears to be no release valve?
Any thoughts?
Post a pic of the other side, the side with the part # on it. The part # should end in 02 or 04.
The white residue is dried anti-freeze. Looks like the cap might have been leaking. The cap can require more force to fully tighten than one might think. Are you sure you screwed the cap down securely?
The part number is 987 106 044 00. I have actually ordered a 996 106 447 04 but I think now that this is the cap under the engine cover, not the boot cap. I'll check again that it's super tight. As I filled it to the max level when it was stone cold I have a feeling it's just expanded and the excess is escaping. I'll keep an eye on it though.
Panic over. I think I just overfilled it a little. Went to check now and when I uncrewed the cap it overflowed. Sitting right at the top of the neck now. I guess it will continue to release a little more once it's hot until it finds its level.
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