# Mysterious dash light

**URL:** <https://community.cartalk.com/t/mysterious-dash-light/62865>\
**Category:** Maintenance/Repairs\
**Tags:** bmw\
**Created:** [March 22, 2011, 12:31am UTC](https://community.cartalk.com/t/mysterious-dash-light/62865 "2011-03-22T00:31:31Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Doctorbill](https://avatars.discourse-cdn.com/v4/letter/d/779978/32.png) [@Doctorbill](https://community.cartalk.com/u/Doctorbill)\
**Post date:** [March 22, 2011, 12:31am UTC](https://community.cartalk.com/t/mysterious-dash-light/62865/1 "2011-03-22T00:31:31Z")

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I have a 1989 BMW 635csi. Usually runs great. Driving down the freeway yesterday, the car started to run rough and the yellow ABS light came on. I slowed, the car ran smoothly, but then the ABS light would come on. By accelerating or decelerating, the light would go off. But in stop & go traffic, the engine ran very roughly and I smelled unburnt or poorly burnt exhaust. Took it to the BMW place today. Runs great. They cannot duplicate the problem. Any ideas?

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**Author:** ![Cole\_s\_Law](https://avatars.discourse-cdn.com/v4/letter/c/f17d59/32.png) [@Cole\_s\_Law](https://community.cartalk.com/u/Cole_s_Law)\
**Post date:** [March 22, 2011, 2:29am UTC](https://community.cartalk.com/t/mysterious-dash-light/62865/2 "2011-03-22T02:29:30Z")

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Well, ABS is your anti-lock brake system, so that light shouldn’t impact how your engine runs. Is it possible that “poorly burnt exhaust” was maybe burning brake pads?

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**Author:** ![Doctorbill](https://avatars.discourse-cdn.com/v4/letter/d/779978/32.png) [@Doctorbill](https://community.cartalk.com/u/Doctorbill)\
**Post date:** [March 22, 2011, 4:30am UTC](https://community.cartalk.com/t/mysterious-dash-light/62865/3 "2011-03-22T04:30:02Z")

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Checked that at the time. Definitely not a brake smell and the brakes were not hot. Braking seemed normal as well.