Mercedes Benz Diesel CDI EGR Emulator Circuit Diagrams
Mercedes EGR Emulator Circuits for Electric Wahler EGR on Diesel Engine For any car fitted with a MAF you can't just block the EGR valve as the MAF detects the reduced airflow when the valve operates. If it fails to report this reduction the ECU throws a code, turns on the MIL light and engages Limp Home mode. The EGR valve is operated in varying degrees whenever the engine is in cruise mode. A circuit has to be designed that reduces the MAF output voltage whenever the EGR valve is called to actuate. Having seen a mod on another forum I decided to give it a go and installed it last night. The circuit is really simple. The EGR valve transducer is fed with constant 12v which is proportionately shunted to Gnd to create the potential to activate the transducer, to engage the EGR solenoid and allow hot gasses into the intage via the EGR valve in varying degrees. The MAF is in the cold air intake. the EGR gasses enter furt...