Originally Posted by Zulfiqar

If thats a 3.1 v6 - I can gurantee that the lower manifold gasket is shot, replace and remember to use proper GM engine sealant or toyota FIPG on the blank space between the 2 gaskets. If you dont and use pep boys/autozone/FLAPS etc gasket maker then you get back to square one faster than a veyron accelerates from 60-100 mph.

The rich running issue is usually a bad MAP sensor or bad fuel pressure regulator.

Another tip - if you are changing the ATF and dont fancy bathing in it then undo the supply line for cooler - (small circlip) and install a hose on it and dump into a bucket. Start engine and allow it to empty the transmission pan for you - now you can get under the car and remove the transmission sump neatly.

If your radiator has the smaller type cooler line fittings then you can buy a barb for it from autozone etc - its about 3 dollars - shove a hose on it and do the same as above.