weird dieing problem...

This problem started about a week ago. At first, It would hesitate harshly until the car warmed up, then it would run fine. Yesterday it got worse. It now dies randomly until the car is warmed up. It wouldn't start for about five minutes after the first time it died.

PS- About four months ago the car got a full tune up (plugs, wires, ff, etc.), new HG's, rebuilt blower w/ a home port, new cam position sensor, and all new belts, along with a ne t-stat.

It seems like a coolant temp sensor problem to me, but I don't know how big of a part those sensors play in these cars. Any ideas you guys could offer up would be much appreciated. Thanks.

How did the EGR valve look? Was it all dirty, might need replacing...Seen these cause stalling issues in other cars. Now that I think about it, it would still start after it died so I think that rules out the EGR. I'm stumped with the not starting for five minute thing.... hmm.....

Egr

I cleaned the EGR valve and all the tubes with carb cleaner during the HG change... and also ported the manifolds and gutted the cats. I have noticed it developing an exhasut leak, could this have something to do with it?

An exhaust leak can cause real problems if it is near or in front of the oxygen sensor.
there is a vacuum in your exhaust a large portion of the time. A leak will allow oxygen to be drawn in and sent past the oxygen sensor. Therefore the PCM reads the system leans and tries to richen an air/fuel ratio that is not actually wrong(if there is nothing else wrong).

I am having to believe that you are on the right track with the temperature sensor though. I would assume that you know there are two: one for the gauge(single wire), and one with two wires for the PCM.

If you have an accurate way to measure temperature I will upload the chart for ohm testing the sensor at a range of temperatures.

I don't think so, that doesn't explain why it doesn't start for another five minutes. It's hard to say, all I can think of is going back over anything you have changed or updated and look for clues there.

Thanks for the help guys

Thanks for all the help, those charts would be really nice to have. You can email them to me if you like @ rdh6d5@umkc.edu. Thanks guys.

if it would run for 5 minutes(approx.), It may have been trying to go to closed loop, and stalled.

It's around there or possibly a fuel pump cavitating, or making a small air draw. It's worth monitoring the fuel pressure.

My SC does the same thing. I know for a fact that my engine temp senders are both bad, the one for the computer is cracked, and the dash guage drives backwards with the key on. After it warms up it idles great,but is shakey for the first few minutes. I think your on the right track with the sensors.

my car hesitates sometimes when cold i blamed it on the fuel pressure regulator stp gas treatment seems to help , it never went bad just sticks sometimes when real cold out , in the morning for first 5 minutes , when my fuel pump was bad it took me a year trying different sensors it would stall when warm after about a half hour at stop signs , finally i put in a fuel pump it was fixed but regulator still acts up now and then without stp gas treatment for a few months