I have an 89 Accord LXI which was supposed to have a tipical B20 engine but engine was replaced with an used engine that looks the same except for the engine ID is only the letters BT. Not B20 or B18? . I am getting a CEL #12 (EGR valve). The valve tested good and just to be sure REPLACED the valve. Still getting the same CEL 12. When I was at the salvage yard I was looking at the same engine, same year and noticed I have an extra vacuum valve gizmo on the thermostat housing. This "valve" has 2 vacuum hoses. One is coming in from the EGR valve itself and the other going out to the control box on the firewall and into the EGR control solenoid. When testing this "valve" there was no vacuum in neither one. Suspecting this valve is not working but wondering if it needs to be normal temperature for it to actuate but then why the CEL 12 again. I runs nice but my gas mileage is not good.
Anyone ever heard of this BT engine????

 

Picture?

 

Your Google search found this... http://www.google.ca/search?sourceid...iw=980&bih=570 94

 

Been busy with Integra LS but will get to Accord the next couple of days and post a picture of the valve. Thanks for the replies. Haynes shows a diagram of a CVC valve being in line with the EGR. Anyone heard of this CVC?