If the car is running and I unplug the egr solenoid on my 305 tpi, should there be a difference in the way it runs? I unplugged mine cuase im having an intermittent problem where the car wont idle on its own more often then not, and I unplugged it and it made no change and still wouldnt idle. Everything else on this engine has been replaced except- egr solenoid, knock sensor, ESC module, and distributor, and ecm. This thing is driving me nuts, lol! Everthing else is new, ac delco parts. All 3 relays, wiring harness is reconditioned, MAF sensor is newer, o2 sensor brand new along with hooker 2055's and y pipe, injectors rebuilt and sonic cleaned, fuel pump and pressure regulator, plug wires, plugs, IAT, IAC, TPS. Voltage is set correctly on tps....I dont get it anymore. Never had a car trick me this much.

 

Keep in mind that I have what was a 305 TPI now converted into a 305 4bbl, but...

Disabling the EGR shouldn't change the way the car runs. It'll change the dirtiness of your exhaust, as I painfully found out come emissions time, but shouldn't cause any motor problems, per se.

 

Are you disconnecting the vacuum or electrical connection. If electrical is disconnected, there may be no change if the solonoid is bad and letting vacuum thru. By disconnecting the vacuum connection, If there is no change with rough idle, could be a stuck valve. I'm not saying THAT'S your problem, just one part of the diagnostic process. The EGR doesn't get a ground signal until in gear with an auto trans, and wheels turning with a manual trans, so no, there should be no difference idling.