brakedrum

Trying to diagnose EGR system to see if it might be causing my drivability issue. Just a quick question. I unplugged the electrical connection on the EGR valve and started the car. The check engine light did NOT come on. I tried shorting the OBD1 tap with a bent paperclip to make sure the code 12 hadn't stored quickly. No codes present. Is it strange for the EGR valve to not throw a code?

92civlude

This ECU will only detect a malfunction in the EGR system when it tries to open the EGR valve. It wont happen just parked and running. You need to drive it a few miles with the connector unplugged. Even so.. A plugged EGR system will never set a code on this car. But a plugged EGR system will give you some driveability issues.

brakedrum

Thanks. I drove about 7 miles earlier with that connection unplugged and sure enough the CEL popped on. That must have been when the system tried to signal the EGR to open and found no EGR. I put the EGR back online. I've decided enough is enough. I'm going to drill out the egr ports this weekend. Probably just going to it quick and dirty by drilling straight through and then busting up the carbon with a coat hanger or pick and resealing the ports with a screw and some jb weld. Might completely pull the plugs next time but for now I badly need the car running right.

jdowen2

Have you cleaned the throttle body and IAC? What makes you think its the EGR?

brakedrum

Cleaned IACV last night. Will be putting it back on when I get home. Hopefully that will do it. I checked the ohms across both iacv terminals and confirmed that both terminals individually do not form a closed circuit when attempting to ground them with the multimeter; everything is in spec' so the valve appears to be good. If cleaning it solves the drivability problem I will be very happy. Although it's an interesting job, drilling/pulling those egr ports was/is not a job I was looking happily forward to.

luded as fuhh

I unplugged my egr 3 days ago, I drive approximately 12 miles to work and still no check engine light. I just got back from about a 40 mile drive and still no CEL, what could that possibly mean? Is there something wrong when I drive for miles without a CEL?