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My '99 996 won't restart when the engine is hot

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

Discussion summary

YOUR RESEARCHMy '99 996 won't restart when the engine is hot

Leading reported evidence

Replace starter

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
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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
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.

Performed · outcome unconfirmed

I let this continue far too long - once I replaced the starter, it became obvious just how poorly the car had been starting, even back when I thought the starter was still "good."

Original post Read captured discussion
My '99 996 won't restart when the engine is hot

Suggestion

5) Replace the starter with brand new Bosch SR0808N

Original post Read captured discussion
My '99 996 won't restart when the engine is hot

Performed · outcome unconfirmed

Same problem, replaced starter, all is well.

Original post Read captured discussion
My '99 996 won't restart when the engine is hot
Frequently discussed work

Check corrosion at terminals and grounds

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

2) Check for corrosion at terminals and grounds

Original post Read captured discussion
My '99 996 won't restart when the engine is hot
Read full discussion summary

Leading evidence: 'Replace starter' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'problem' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Check corrosion at terminals and grounds' (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

problem

Suggestion or failed attempt

No successful repair reported for this finding.

0
Identified cause
1
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 suspect 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.

Suspected cause

The starter is more likely the problem.

Original post Read captured discussion
My '99 996 won't restart when the engine is hot

Check corrosion at terminals and grounds

Suggestion or failed attempt

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 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

2) Check for corrosion at terminals and grounds

Original post Read captured discussion
My '99 996 won't restart when the engine is hot

Check voltage drop

Suggestion or failed attempt

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 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

3) Check for voltage drop from battery to engine terminal

Original post Read captured discussion
My '99 996 won't restart when the engine is hot

Clean lube will fix it

Suggestion or failed attempt

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 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

Often a remove,clean,lube will fix it - for a while.This link is old but will get you started :-)

Original post Read captured discussion
My '99 996 won't restart when the engine is hot
Frequently discussed actions (6)

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

Check corrosion at terminals and grounds

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

2) Check for corrosion at terminals and grounds

Original post Read captured discussion
My '99 996 won't restart when the engine is hot

Check voltage drop

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

3) Check for voltage drop from battery to engine terminal

Original post Read captured discussion
My '99 996 won't restart when the engine is hot

Clean lube will fix it

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

Often a remove,clean,lube will fix it - for a while.This link is old but will get you started :-)

Original post Read captured discussion
My '99 996 won't restart when the engine is hot

Inspect there

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

Start search/inspecting there?

Original post Read captured discussion
My '99 996 won't restart when the engine is hot

Replace starter

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
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.

Performed · outcome unconfirmed

I let this continue far too long - once I replaced the starter, it became obvious just how poorly the car had been starting, even back when I thought the starter was still "good."

Original post Read captured discussion
My '99 996 won't restart when the engine is hot

Suggestion

5) Replace the starter with brand new Bosch SR0808N

Original post Read captured discussion
My '99 996 won't restart when the engine is hot

Performed · outcome unconfirmed

Same problem, replaced starter, all is well.

Original post Read captured discussion
My '99 996 won't restart when the engine is hot

Replace y-cable

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

4) Replace the Y-cable

Original post Read captured discussion
My '99 996 won't restart when the engine is hot
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.

problem

No successful repair reported for this finding.

0
Identified cause
1
Suspected cause
0
Reported fixes
Read evidence and context
Discussions that suspect 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.

Suspected cause

The starter is more likely the problem.

Original post Read captured discussion
My '99 996 won't restart when the engine is hot
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.

  • Rennlist: 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: 20261027T044418Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

I have a '99 996. Standard 3.4L with no mods. 6-speed. It won't restart temporarily when the engine is fully warmed-up. If I shut it down to pump gas or something, when I try to start it a few minutes later, it turns over once only and doesn't catch, then silence. It's like the battery is really low on charge or something. But then, when it cools off for 10 more minutes, it turns over (a bit slowly) and starts up. When it's cold -- or has even just cooled off for 10-15 minutes -- there are no problems whatsoever. (And I drive it through South Dakota winters -- it gets pretty damn cold. The car has started fine at -24 degrees.) The battery is less than a year old.

POST 2Original post

Heat related high resistance to/in the starter motor? Start search/inspecting there? Common failure mode of an old starter motor or starter motor relay or solenoid. Often a remove,clean,lube will fix it - for a while.This link is old but will get you started :-) http://forums.pelicanparts.com/porsc...d-finally.html Someone may have a version for the 996?

POST 3Original post

im voting starter motor. its almost 20 years old by now.

POST 4Original post

Search for some of Ahsai's threads. He gives good instructions on how to properly analyze your issue. My vote is generally always for the alternator-starter Y-cable, but you should diagnose it first.

POST 5Original post

I let this continue far too long - once I replaced the starter, it became obvious just how poorly the car had been starting, even back when I thought the starter was still "good." "It'll start fine after another few minutes" is totally fine for me, but not OK for my wife if she's out somewhere at night. The issue does get progressively worse...if you're just now starting to have hot-start issues, get crackin'!

POST 7Original post

Another thing to check, that is quite easy to replace, is the crankshaft positioning sensor. They are prone to fail with age and can give the same symptom. I had the same problem with my car not starting when hot and have replaced mine. /C

POST 8Original post

1) Make sure the battery is in top condition 2) Check for corrosion at terminals and grounds 3) Check for voltage drop from battery to engine terminal 4) Replace the Y-cable 5) Replace the starter with brand new Bosch SR0808N CPS is often a culprit in a "it cranks hard but doesn't start" scenario The starter is more likely the problem. Same problem, replaced starter, all is well.

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