Is there an intake air temp sensor on the 3.1s? I purchased the car and it didn't have the intake on it. Just the ribbed hose with a filter dangling off it. I see an end of an electrical connector where the filter housing used to be located. I assume if there is an air temp sensor it plugs in there? Its about 6 inches away from the coolant reservoir. My haynes manual says nothing about the sensor anywhere so if said sensor does exist on this model what should I buy to replace it?

go to autozone.com or rockauto.com and see if they have a part number listed.

Yea they had it listed, picked up the part and ran it to the intake.
Cleared my CEL and now im havin no codes. To bad the engine developed a knock.

just a little FYI: they have the IAT in the filter housing. I still have the stock intake system and sensor. It shouldn't have started knocking because of that. I'm not really sure why that happened.

Oh, I didn't mean to imply that it caused the knock.. Just seems like one problem after another.

As far as the IAT.. its been bought and plugged in. Got rid of both CEL codes. Now on to the bigger problems.

i was about to say i also have the entire stock intake setup w/temp sensor

Is it a knock or a ping...they are 2 different things often falsly described the same. The installation of the IAT can cause a ping since the ECM defaults to a rich codition in the absence of an IAT signal, which can cause carbon deposits on the back of the intake valves and tops of the pistons. This causes hot spots inside the cylinder, but the rich condition keeps the ping to a minimum. Once you install the IAT, the ECM goes back to it's "lean" state and the hotspots inside the cylinders cause a ping. If this is the case, then try running some seafoam or something down the intake.

Good luck.

I have no experience with either knocking or pinging noises so I doubt I can differentiate the two. Ran sea foam through the break booster vac line a few weeks ago so unless it has alot of new carbon buildup it may not be the problem. I think the problem may be thin oil, had extremely old coolant that caused some good overheating problems, think i cooked my oil.