P0128

Hey everyone i have an 03 impala with the 3.4 engine and my check engine light comes on but only when it real cold i flushed the radiator a few weeks back and the temp stays real low on the highway but when its cold is the only time it stays really low causeing the light to pop so i am gonna change my thermostat but there is a pipe from the exhaust that runs behind it what would be the easiest way to remove it do i need to take that pipe off

I've heard it can be done without removing the exhaust crossover, but save your self some time and trouble, and remove it. It's easy to remove and reinstall, and makes the T-stat job go a lot quicker.
Also, try using some punctuation. I had to read your post 3 times to figure out what you were trying to say!

Correct, reasonable grammar is expected on the forum, thanks.

Sorry about the punctuation. And so it would be easier to take the pipe off? Alright thank you for the help

Yes, just be careful in order to facilitate reinstallation.

A little WD40 on the bolts will help, but expect to smell it a little the first time the exhaust gets hot.