After searching the forum I still can’t find my answers. My 95 x300 4.0 6cyl’s smog pump is electric (& I “think” its not functioning anyway), no belts, pulleys or hoses that I saw, probably connected to the computer via the plug. My questions are what’s the best way to eliminate the pump, just unplug it ? I read the “check engine” light will come, so just erase via decoder ? If its’ connected to the computer will “unplugging” create fuel mixture, Ox sensor, exhaust, ignition problems? BTW no IM in Florida. Thanks
I seem to remember that the pumps were made by ELECTROLUX and the only purpose they serve is to help the cataverter heat up quickly at engine startup to satisfy emission standards.
Pumping air into the exhaust at startup is controlled by the ECM and you will get a fault (MIL) if the air is not detected.
I even installed one on the AJ6 4.0 engine instead of the belt driven pump. I used a relay in the circuit where the clutch actuator was wired.
In the UK, on my 96MY the engine light does NOT come on when the pump is disconnected, allowing for the fitting of SS headers without the air feed.
I don’t know were you are from so just unplug it and see what happens!
Also it would help if you edited your profile to show a location flag