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Q: ASR light on dashboard and car runs slow - 1992 Mercedes Benz 500 SEL

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My older model car is in mint condition and everything is working well except that two to three months ago the ASR light (Automatic Slip Regulator, aka-traction control) started appearing on the dashboard. I turned the car off, restarted it and everything worked normally, but after having used the brakes a few times the ASR blinked on again and the car slowed down a lot. It only moves at amount 10% of its power. Three weeks ago the ASR light started being continually on, no matter what I tried. I replaced the gas pedal with a refurbished one and it is still rough. I also checked the gas pedal cables, checked the wheel sensors, and ran a computer scan almost every day for the past month. Now, the cruise control is not working. A technician suggested that I replace the whole wiring system in the car, but that is a major job. What do you suggest I should do first and then after that?

A: You may want to get a second opinion before...

You may want to get a second opinion before replacing the entire harness. You could start by first checking and cleaning the mass air flow sensor of any dirt and oils. The sensor will cause the loss of power and ASR activation. Make sure there is no leaks in the hoses from the mass air sensor and the throttle body. If you still have problems, then contact a Mercedes mechanic to diagnose the warning light for further repair.

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