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Bosch Spark plug questions

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5 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

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YOUR RESEARCHBosch Spark plug questions

Leading reported evidence

Check coil and plug

Suggestion or failed attempt

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Reported fixes: 0
Unsuccessful attempts: 1
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Discussions that contain suggestions: 1

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Suggestion · Original poster
I was checking the coil and plug.
Original post Read captured discussion
Bosch Spark plug questions

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Leading evidence: 'Check coil and plug' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check coil and plug' (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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Run r5 plug

Suggestion or failed attempt

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
Misfires have occurred running the R5 plug.
Original post Read captured discussion
Bosch Spark plug questions

Frequently discussed actions (2)

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Check coil and plug

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
I was checking the coil and plug.
Original post Read captured discussion
Bosch Spark plug questions

Run r5 plug

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
Misfires have occurred running the R5 plug.
Original post Read captured discussion
Bosch Spark plug questions

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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.

5 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: 20261026T200546Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

I installed new Bosch plugs FGR-6-KQE is my 99 c2 about 4months ago along with new Bosch coils. Ran fine. The other day I got a misfire code with a CEL for cylinder 2. I was checking the coil and plug. I noticed the spark plug said R5 printed on it. I thought these for a 6 heat range. If these are 5 are they ok to use? The ones I removed were printed R6 and were Beru. Thanks for the help Joey

POST 2Original post

I am pretty sure you need the R6. Misfires have occurred running the R5 plug. Other folks here can chime in to confirm.

POST 3Original post

Yes I had this exact issue with Bosch plugs from summer 2020 through Fall 2021. My Bosch also were printed with R5. I don�t know if that relates to their heat ranges (which would be the wrong range if true) but the misfires stopped when I went back to the Beru plugs. https://rennlist.com/forums/996-foru...-detailed.html

POST 4 / ORIGINAL POSTEROriginal post

I called Bosch and the R5 and R6 are production numbers. Not the heat ranges. But it is still strange I have a pop up misfire after installing these. I am still investigating it. Going to switch coils with another cylinder then change out plugs next. Joey

POST 5Original post

It may be a problem with that particular production lot

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