Nissan BPT valve

Anyone have trouble with one of these? My 97 Hbody is giving an EGR code and my local stealership said that it is the BPT valve and said it would be about $250 to replace! I found one on-line for about 50 bucks but have no idea where it is or how to replace it.

DO YOU KNOW WHAT THE CODE IS EXACTLY?

My frontier threw up the egr code a while back. All I did was compress the diaphram on the egr valve a couple times, and then reset the computer. The code hasn't came up since. Your egr vavle should be located just behind your intake manifold.

I don't know what the exact code is, apparently its top secret info that the dealership won't give out in fear of compromising national security. All they said was that they wanted to replace the BPT valve and recheck the system.

buy a haynes manual, it will show you how to get the codes off of the computer. Your check engine light will flash in sequence to give you the code.

Yeah so I found and replaced the BPT valve and the three lines going to it and cleared the check engine light. The light came back on with a P0400 code which is "exhaust gas recirculation flow malfunction". What's next? I was thinking the EGR valve since it is in line with the other valve that I already replaced. Any thoughts?