Ok, l don't have a clue. I have a 03 Monte Carlo SS with 3.8. My wife was driving and it quit on her, she said like someone had turned off the key. I told her we needed a fuel pump. Got a new pump, started right up, and I thought I was pretty smart! l drove it to the store about 3 blocks, shut it off. drove it back home, no problems. next time I drove it about 4 hrs later, it ran fine for about a mile and then it started surging. The car was actually lurching forward and the rpms would jump up and down. If you accelerate the car it would run fine, the speed didn't make any difference. If you tried to maintain current speed it would serge, again speed didn't make any difference. the car died several times driving about 10 miles. Ever time it died you could shift to neutral and it would start back up. I immediately suspected a bad fuel pump.
Next morning, same thing. Started right up and drove fine for a mile. Then the lurching and dying started again. Anytime you let off the accelerator, it would die. I drove to mt buddy's house about ten miles and shut it off. Started up, ran fine for a mile then started all over again. it died several times on way home but always started. I pulled into the drive it died again and wouldn't start. While I was at my friends, we took off fuel filler cap and you could hear a buzzing inside, as if the pump was running with the key off.
So the car died and wouldn't restart. with all the restarting, the battery was weak. Put a charger on battery and the car would turn over but would not start.
I thought it was fuel pump. Couple of days later, I pulled the pump and exchanged it for another. Put the new pump in, you could hear it pressure up, but the car would not start. I pulled all the plugs one by one and have spark. I did the diode tester on the injectors, they are all getting even pulses. I have recently replaced injectors with remanufactered ones from Rockauto.
My headlights come on when key is turned.
Battery is fully charged.
The engine turns over but will not start.
I plugged in scanner and got the following codes
452-Fuel tank pressure sensor current low
128-Coolant termostat
300-Random cylinder misfire
I pulled the IAT sensor and the end of it is bad to the naked eye so I am pretty sure that is the reason for the 0128 code.
I am stumped. I am frustrated. I am ready for new ideas.

 

Sorry to hear about the trouble you are having with your Monte. You have given a lot of good information and I am sure that someone here on the forum with much more knowledge than I will be able to give you some insight.
Anyway, I just wanted to say Welcome to the forum!!!!

 

Question..
When you changed out the fuel pump..
Did you also change out the fuel filter?
Try checking the fuel pressure at the fuel rail..

 

The filter was changed in October with the last fuel pump. I checked it. It has no restriction at all, like blowing through a straw. Thanks for the welcome. I have been lurking here for about 6 months. It took this to get me to register. Lol

 

Checking the fuel pressure at the rail was my next thought. If I have too little pressure. . . What is next step?

 

It could be that there's an obstruction in the fuel lines..
Provided the fuel filter is still free flowing..
With a full pressure from the new fuel pump it may have picked up some residue/dirt from the tank.. Thus plugging the system/filter.
I would suggest/recommend rechecking the fuel filter.

The common cause of this is from regularly running your tank down to below 1/4 tank...
should you find that the fuel line is clogged, disconnect the fuel line at the fuel rail.. and use mild air pressure to try to clear the line... I would even consider running some seafoam cleaner through the system as well.

Keep us posted of your progress and what the problem was/is...
Were here to help!
Thanks for joining the MCF Family.

 

Okay STUMPMI, I will try these suggestions. Lol, I have been reading your posts all day long it's almost as if I know you. How much pressure should I have?

 

It should be 41psi

 

By George I think I've got it!
I was set to get a pressure gauge and put on the car. But I would need to get a ride 17 miles to get a gauge. I decided I would blow out my lines first since I could do this without going to town.
I disconnected my line a had a buddy hold a white rag below the line to catch any grit that might come out. We got a clean rag and clean fuel to come out the line.
We blew out the return line with the same results.
So now I'm standing there scratching my head and I decide to turn on the key with the line disconnected from the filter. We get squat. No fuel out of the open line.
So we blew out the line from the tank to the filter. No restrictions.
Since I had to line from tank disconnected I decided to hook a 3/8 clear hose I had directly to the pump. Turned the key on and NOTHING.
So now I am headed to town to get yet another pump.
This current pump has never run in the car.

 

Ok. So I feel better than I have in days because I think I have this licked. I get to parts house and they have to order another pump. Ugggh!