8 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHstumble when cold under moderate throttle
Leading reported evidence
Replace spark plugs about 5 years and 50,000 miles ago
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 · Original poster
I replaced the spark plugs about 5 years and 50,000 miles ago but I've never replaced the coil packs...you see where I'm going with this.
Leading evidence: 'Replace spark plugs about 5 years and 50,000 miles ago' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace 4' (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
Or you can wait until one throws a code and then replace all 4.
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.
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
If you are feeling in a preventative maintenance mood replacing the O2 sensors may be a good idea.
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.
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: 20261026T174436Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Driving home tonight in the cold rain and the car stumbled a few times at about 3000 rpm about 1 kilometre into it.
It felt like a miss but the car did not throw a CEL.
I pussyfooted a few kilometres and after that the stumble was gone.
Drove home the rest of the way (about 37 kilometres) under both moderate and hard throttle without issue.
2002 996 with 232,500 kilometre on the clock, but a factory reman 3.6 litre was installed in 2005 at 70,000 kilometres.
Translation is that the engine has done 100,000 miles.
I replaced the spark plugs about 5 years and 50,000 miles ago but I've never replaced the coil packs...you see where I'm going with this.
Does the symptom as described sound like coil packs to anyone out there...?
On a related note......would the car have thrown a code without also lighting up the CEL ? I have access to a scanner ...
Thanks
Assuming the CEL is not "burned out" no CEL no code. There may be a pending code however.
100K miles and driven in sloppy weather my advice would be the same as others have offered: coils. Coils and plugs. At 50K miles the plugs don't have much service life left and you might as well start the new coils out with new plugs and be sure the correct plugs are used. Now is not the time to begin experimenting with spark plugs.
If you are feeling in a preventative maintenance mood replacing the O2 sensors may be a good idea. Or you can wait until one throws a code and then replace all 4.
Thank you for that Macster. Pretty much what I was thinking....plugs and coils. The stumble did not present this morning so maybe the problem isn't serious enough yet to throw codes.
I have set of plugs and coil packs in my shopping basket at Pelican already, but I hadn't thought about oxygen sensors.... You say there are 4? I only see connectors for 2.
Will do some digging....
On my newly purchased 99 C2 I was getting similar issues when it was anywhere from 25F to -20F , it would stumble and be rough in idle for say 1km and then drive normally. When I would leave work from the heated parkade it would never stumble . If I continued to push the engine in that 1km it would throw a flashing CEL which was a cylinder 4 misfire.
I replaced the plugs and the cold weather stumble hasn't returned in the last 2 weeks. Cylinder 4 did have a leaking spark plug tube which I also changed.
I scanned the car, no codes. Has been running like a top as well.
Nevertheless... I consider this a shot across the bow. Plugs and packs are on the way.
Thanks guys. I will report back if anything more develops.
* it's definitely not bad gas......
This is a source reference. Confirm exact model applicability in the original material.
