Tagged: EHA

November 27, 2020

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...

Mercedes

November 20, 2019

KE Jetronic EHA Adjustment

I discovered at the MBCNSW Dyno day that my 560SEC was running dangerously lean. Lean enough to cause damage to the engine. While I was in the USA for work, I went to the Mid Florida Auto show. I met Pierre Hedary there (who runs an independent Mercedes workshop), who suggested that I should start by testing my fuel pressures and that he had...