47ish thousand mile 2002 XL7 with the 2.7L V6 and automatic.  Well cared for, runs well, and hasn't given us any noticeable trouble in the year we've had it now.

Monday morning my wife calls and says the check engine light is on.

Sigh...

After a debacle with my own code reader's faulty programming last night I managed to get the codes read today at Advanced and the code is the P0401 EGR flow insufficient code.

I'm curious because some of the parameters it has regarding intake air temp and engine coolant temp for testing it could have possibly been below minimums as yesterday was very cold in the morning.  It had sat all night in the unheated garage and it might well have been very cold when it started and perhaps caused a false reading?  Starts up and goes just fine right now.  Had the code turned off at Advanced and after about 20 miles and two starts the code hasn't returned but it's also a bit warmer...right about freezing.

Anyone had to mess with this code and it's fixes?

no info on codes but I can tell you mine has come on during cold spells, then goes away after a day or so.

Thanks, I'm thinking it's something to do with the cold.  I had the codes reset on Tuesday night and so far no repeat of the light coming on.  I think the computer farted.

   Sorry.That was me.