Ok, got a code 23.... changed the TPS, reset the comp, and still code 23. Must be the MAT sensor. I bought one, now where the heck is this thing on my engine. Is it under the plenum???

 

Yep, screwed into the bottom of the plenum.

 

make sure you unclip the MAT before giving your plenum a big tug.. (ie. unbolt the plenum, lift it up, unclip)

if you break that clip you can get a new one from GM for about 10 bucks (that's what i did)

btw: that's a 'great' time to change your EGR, get a GM one, it's worth it

 

I was thinking that this is a great time to install an afpr, port my plenum, polish or powder coat my runners, and clean my plenum and intake manifold real good. What do you think? As far as the EGR is concerned, should i replace it even if it works fine? The car has under 40K on it.

 

40k is nothing, it should be fine..

i dunno, whenever i'm doing a job and could go the extra mile i do it but your car is so low miles i wouldn't worry about it