Hello all , new member here, I have a Red 95 sc400 ,104k miles,second owner runs great, t belt, serpentine,sparks ,wires caps rotors and alternator recently done. Has had code 71 ( EGR ) since I got it, hasn't effected performance, again drives like a dream and I have another sc400 and have driven many so I know what good is. Have had two used Oem EGR valves installed to no avail! Shop I trust for everything diagnosed valve as being the problem, not opening enough,but I'm wondering maybe it's the ECU ? I wonder because the valves I got come from cars who's owners I know who didn't have any engine codes. Please help if you have any theories,I'm in Cali ,bay area so smog is an issue here so I can get get this gem registered. Thank you all! Btw there are two EGR valves, one with coolant tubes facing same way, another where they face different directions, these face the same way.

 

Bump? Anyone encounter this before? Am I just getting unlucky with these used EGR valve or could it be something more? Thanks

 

Delete the EGR valve and system, it’s an OBD 1 so it won’t throw a dummy light

 

As good of an idea that sounds in theory I'm not sure I could pass smog like that here in Cali