Computer control of engine operation requires a completed 'loop' to properly make needed adjustments. For mixture control, the O2 (lambda) sensor is the input to the loop that tells the computer whether the mixture is too rich or too lean. The EHA is the electro-hydraulic device by which the computer makes the necessary adjustments to get the O2 sensor reading back into the correct zone.

Steve

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'91 MB 190E 2.3
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