560SEL EHA replacement
Today’s job was EHA replacement (Electro-Hydraulic Actuator) on my 1987 560SEL. The EHA is part of the KE Jetronic fuel injection system and makes minute adjustments to the air/fuel mixture. One of the sources for these adjustment is the oxygen sensor, if present. The EHA can leak either because the o-rings between the EHA and the fuel distributor have gone hard, or because of...