Saturn Repair: car almost stalls upon acceleration from stop, valve cover gasket, vacuum leaks

Question
QUESTION: I have a 97 Saturn SL 2 152k mi. I myself, have replaced the ENTIRE fuel system including injectors and plugs and wires. The car still bogs   down to the point of stalling upon acceleration from a dead stop.( scary in traffic ).When it  stalls, i have to give it full throttle to get it to re-start ( hard start ) and then it blows white smoke from tail pipe and it smells very rich. I have also replaced the head gasket because of oil in coolant and the valve cover gasket because of a minor oil leak. Once the car is running down the road you would think you were in a brand new car( everything is perfect!) One other thing, sense i did all this work the temp. gauge barely registers above the C although the heater works GREAT. Could this be as simple as a ECT sensor , a bad coil, or throttle body. Any ideas would be of great help. I am at wits end and tired of buying parts that dont fix it.Thanks in advance, Bob. PS cat. converter ?

ANSWER: First thing scan for codes. If you don't have a scanner your local auto zone usually does it for free. Then get back to me.

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QUESTION: have already done that and have no codes

Answer
Did you use oem parts directly from your saturn dealer? Ive seen alot of issues with aftermarket fuel pumps having excessively high fuel pressure. Check the fuel pressure with a gage. Also the ect sensor fails alot on these cars. If it is original i quarantee that it is bad. Remove the sensor regardless and check the tip. If the tip is plastic then it is the old style. If the plastic tip is cracked at all its definately bad and in that case you will need to replace the ect sensor and the connecter to! The new ect sensor will have a brass tip. You did alot of work to the car are you sure the timing is dead on? Are there any vacuum leaks. Make sure the throttle body is clean and not carboned up. Check the iac valve for excessive carbon around the pintle and throttle body seat for the pintle. Remove your linear egr valve and gently push in the pintle valve. It could be completely stuck shut! Then you will need to replace that. I mentioned everything i could think of that would cause this with possibly not setting a code. So check it out and please keep me informed! Also pull the plugs out and inspect them and let me know what they look like.