My 91 740 is returning a 3-2-1 code that references the Cold Start valve...last time this happened my mechanic said the valve had been disconnected somehow (I think during service elsewhere), and just reconnecting it put everything right. So I'd like to see if I can set it right myself before bringing it in. The problem is, I'm not sure where I'm looking! Can anyone point me in the right direction here? Here is my engine compartment: