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If exhaust or cats bad, will it hurt to drive it?

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

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Discussion summary

YOUR RESEARCHIf exhaust or cats bad, will it hurt to drive it?

Leading reported evidence

Run like crap and could damage internal engine components

Suggestion or failed attempt

No successful repair reported for this finding.

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Unsuccessful attempts: 1
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Suggestion
Too lean and the engine will run like crap and could damage internal engine components.
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If exhaust or cats bad, will it hurt to drive it?

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Leading evidence: 'Run like crap and could damage internal engine components' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Run like crap and could damage internal engine components' (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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Use those values

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Discussions that contain suggestions: 1

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Suggestion
Bad cats will make the O2 sensors miss read the exhaust stream and the DME uses those values to determine fuel mixture.
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If exhaust or cats bad, will it hurt to drive it?

Frequently discussed actions (2)

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Run like crap and could damage internal engine components

No successful repair reported for this finding.

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

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Suggestion
Too lean and the engine will run like crap and could damage internal engine components.
Original post Read captured discussion
If exhaust or cats bad, will it hurt to drive it?

Use those values

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
Bad cats will make the O2 sensors miss read the exhaust stream and the DME uses those values to determine fuel mixture.
Original post Read captured discussion
If exhaust or cats bad, will it hurt to drive it?

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

Rennlist: 1 discussions

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POST 1 / ORIGINAL POSTEROriginal post

03 996, all stock except it has the Fiskar exhaust. If the cats or mufflers are going bad internally, will it hurt the engine to drive it? (other than it being a little louder)

POST 2Original post

Mufflers...no, except if it is broken internally and shows signs of excessive back pressure due to blockage. Cats...yes. Bad cats will make the O2 sensors miss read the exhaust stream and the DME uses those values to determine fuel mixture. Too rich and the cylinder walls get washed down with fuel (instead of maintaining the oil film). Too lean and the engine will run like crap and could damage internal engine components.

POST 3Original post

Quotes source post: 15325761

Over what period of time before any damage occurs?

POST 4 / ORIGINAL POSTEROriginal post

I would imagine it would take a while, and since I drive 80+ miles a day, I'm going to let it sit till it's fixed. I banged on the mufflers and cats, no noticeable strange noises.

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