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Old 02-06-2023, 02:54 PM
nick325xit 5spd nick325xit 5spd is offline
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Quote:
Originally Posted by 80stech View Post
There is a ton of stuff that can cause this but often overlooked is a missfire due to a weak coil or poor spark plug. A compression test would probably be a good idea. Worn valve guides could be another issue.
This is a good point. Misfires can be read as too rich, causing the car to lean out until it causes more misfires in other cylinders.

Injectors are a potential cause there too. A LEAN misfire looks like a RICH condition to the O2 sensor.
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