2001 gtp dies when starting up?

I seem to have a problem when i start the engine and it either dies right away or runs really rough for a few minutes. Has died in traffic at stop signs but runs good during normal use at speed. Have replace the fuel filter and the IAC sensor. I have read on here that if it was the MAF senser i should be able to start the car and it would run fine if i disconnected it before start up. I have tried that to no success. My question is could it still be the MAF senser even when its uplugged during start up? Or could this be a bad IAC sensor that i replaced?
also have checked the pvc and was dirty but could still hear the rattle, and used carb cleaner and cleaned it and put it back in still no difference.
2001 GTP 140k supercharged 3.8

Does the ignition key have a resistor pellet or is it stamped PK3?

Does it start and immediately dies? Turn key to on.....does SECURITY light go out after 5 seconds? If it does will it crank and start?

Has died at stop signs....does it restart right away?

Have you checked for codes?

If it doesn't start, check for spark, injector pulse, and fuel pressure.....if no fuel pressure, before condemning the fuel pump, see if the vehicle has a ceramic inline resistor for the fuel pump circuit....but usually when that goes, it won't start at all....also try spraying carb cleaner into the intake, if you have a no start, but you have spark and no fuel pressure.....

Welcome to the forum Albert!

The problem happens every time you start it up or only during the first cold start in the morning?

I would check the ECT sensor connections and operation. Inspecting the thermostat would be a good idea too, it happened to me that a failed open t-stat caused my car to stumble only during the first startup every morning.

Oscar.

Olopezm, I can understand a starting problem on a cold engine, if the ECT is bad and saying the engine is warm, causing the PCM to lean out the engine and cause a hard start......

But I don't understand how a failed open thermostat can cause a hard start first start of the day.....

Honestly, I keep asking myself the same question.

This is the first time it ever happened to me, I've run cars without a thermostat and never had a problem before. I used to have an hypothesis that the open t-stat would cause an air pocket to build at the ECT and when coolant started flowing and touching the ECT might cause a sudden change causing the problem. After all, engine temperature is supposed to increase slowly.

Anyway, I only know about it because it happened to me. Otherwise I wouldn't mention it.

Oscar.

No the car, isnt always hard to start on the first start up. Sometimes it starts and seems to run fine. Then on errands around town after shutting off and letting it sit for a while, on restart it sounds really rough for a while. (engine rpms go up and down while at idle) it may die or run like that for a little bit, but then smooths out and sounds normal.

The frustrating part is that it doesnt happen every time i start the car. It can be the first start of the day or the second or third time. Then after it smooths out it runs fine until i shut it off, however I have noticed that during idle while driving around town, it sometimes sputters and the rpms bounce around a bit. When that happends it usually just a quick back to normal after the first or second rpm jump.

Thanks for the idea of the the t=stat and the ECT sensor. The car does have a 140k on it and pretty sure it still has the orginal t-stat on it, wouldnt hurt to change that out.
will give that a try.

My 2 cents worth: Sounds like the fuel pump to me. I've replace a few that exhibited same the exact symptoms you describe. Since it's starting, the fuel resister can be discounted. If it was running rough and more than likely the ICM had a problem, the ECM would have thrown a random miss-fire code. No spark would have thrown a miss fire code on the cylinder(s) affected. But the magic number you provided that tells me to swap the fuel pump is the 140K you wrote here. That's when the majority of my fuel pumps seem to go out on my GPs and my Bonnie --- right around 135-145K.

Hey albert.iowa -
Did you resolve the sputtering issue? I replaced the fuel pump/filter and have the same issue of it randomly having rough idle on start up.

Hey albert.iowa -
Did you resolve the sputtering issue? I replaced the fuel pump/filter and have the same issue of it randomly having rough idle on start up.

Welcome to the forum!

You could try removing and cleaning the IAC valve and throttle body and see if it improves.

Oscar.

3 STEPS TO DO Check all fuses,,,,,,,,,,,,,,, unplug MAF does it stay running and I just fixed one today take out High Pressure Fuel Pump relay and bend PIN # 2 sideways,,, plug back in,,now runs fine... That by passes the Dual stage high pressure fuel pump and lets it run fine,,,,, now your choice leave it that way or replace Resistor which is buried below the pass side headlamp. I've fixed a few of these over the last years and just left the pin bent in the relay.