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Engine Roughness and Bumping

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YOUR RESEARCHEngine Roughness and Bumping

1 matching discussions were examined; no attributable action/outcome evidence was detected. No consensus or repair conclusion is claimed.

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1 matching discussions · 2 captured posts examined · 0 partial discussions

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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.

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

Rennlist: 1 discussions

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Generation: 20261026T135432Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Whether on the freeway or around town, I get a "bumping" sensation through the drivetrain and engine similar to an AC compressor cutting on and off in a less powerful car. It happens randomly enough to prevent it from being duplicated at will. The AC on my car is not turned on. The car is an '03 Targa with 2000 miles on the clock. It has not set a CEL and the dealer can't find any faults through the computer. Anyone ever have a problem with their car bumping or lightly surging like this? Any ideas or solutions? Dwayne

POST 2Original post

If it happens at 3K rpm, its the VarioCam Plus kicking in. If you have your foot down it happens so fast you don't notice, if you are just motoring along, it feels like a surge at 3K. I can tell when I hit 3K without looking down... If it's not that, I have no clue what it is... Good luck. Roy

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